0036 – Geophysics at Monte do Olival 1

A first glimpse into the results obtained by the NIA-ERA project directed by me and with Helmut Becker responsible for the geophysics.

0035 – Porto das Carretas walled enclosure

Plan of Porto das Carretas after Soares & Silva, 2010.

Location: Mourão municipality, Évora district, Alentejo, South Portugal)
Chronology: Chalcolithic
Bibliographic references: (Soares & Silva, 2010)

Located on the top of a small hill in the left bank of the Guadiana river, the site is today totally submerged by the Alqueva dam.

Two phases of occupation were detected, separated by a period of abandonment. The first phase was related with a construction of a walled enclosure, with three rows of stone (and possibly also earth) walls interpreted as fortifications. Only the plan of the interior one is partially available, and is composed by strait walls suggesting a polygonal shape, with a bastion in one corner. This phase is dated from the first half of the 3rd millennium BC.

The second phase is related to the construction of several connected circular stone structures. A central one (with entrances to three of the others) is considered a “tower”, while the rest (some of them of the same size) are considered huts. This reoccupation of the site is made over the ruins and abandonment levels of the first phase, is dated from the second half of the 3rd millennium BC and associated to the presence of bell beaker pottery (International style) and copper metallurgical work.

On the other side of the river, just 15 kms away, stands the large set of enclosures of Perdigões, older than Porto das Carretas (started at Late Neolithic) and contemporaneous of its both phases of occupation.
Nevertheless, a “world of differences” separates the two sites. Architecture, dimension, duration, topography of location, relation with funerary practices, evidences of connection with distant regions, etc. And another “world of differences” occurs today in the interpretation of those dissimilarities.

0034 - Summer solstice

Summer solstice, seen from the chalcolithic ditched enclosure of Monte do Olival 1. Geophysical prospection of this set of enclosures started precisely at 21 of June and the ongoing research will determinate if this important annual moment was significant for the architecture, location and orientation of the ditches.

0033 - Horta do Albardão 3 ditched enclosure

Excavation area (after Santos et al. 2009)

Location: Évora municipality, Évora district, Alentejo, South Portugal)
Chronology: Chalcolithic
Bibliographic references: (Santos et al. 2009)

Horta do Albardão 3 is a recently detected enclosure defined by, at least, one ditch.
The ditch is 2,2 meters wide and 2 meters deep, with a section in a slightly asymmetric “V” with a strait base forming a rectangular segment, similar to ditch 4 of Perdigões. It was excavated by Arqueohoje Lda in the context of rescue Archaeology. As usual in Portugal, the excavation and research done was restricted to the affected area. So, just a very small section of the ditch was excavated and no further work was required to determine or infer the size or shape of the enclosure. Nevertheless, the segment excavated seems to indicate a sinuous smoothly wavy ditch, like the one of Perdigões and others.

The ditch was dated from the second half of the 3rd millennium BC (Middle/Late Chalcolithic). Next to the ditch, a funerary pit with a human inhumation was dated from the Bronze Age.

In Iberia, the building of ditched enclosures seems to have stopped during the Chalcolitic, precisely during the second half of the 3rd millennium BC. Nevertheless, some evidences are slowly starting to appear, showing the presence of materials or specific contexts of Bronze Age in some of these sites. The same is happening in Perdigões and in Outeiro Alto 2. Except for the later, data is quite scarce yet to allow any consistent interpretation of those presences. But it is gradually becoming clear that at least some ditched enclosures, deactivated and “abandoned”, still mark the landscapes and the social memory with significant capacity of attracting the Bronze Age communities, namely to burying their death.

I called this circumstance a symbolic extend (Valera, 2003) that makes a site socially active after the abandonment related to its original context of function and meaning. A memory is not simply a passive bank of data, but one of the most active “tools” that frames human action. And sites like enclosures, ditched or walled, have the potential to be what the cognitive sciences call external memory and develop powerful means of attraction. I will be back to this issue.

References:
Valera, António Carlos, (2003), "O abandono de povoados fortificados calcolíticos no Ocidente Peninsular", ERA Arqueologia, 5, Lisboa, Colibri/ERA Arqueologia S.A., p.126-148

0032 - Making them visible

Helmut Becker at Moreiros 2.

In the archaeoastronomy of enclosures project in course, we have been using geophysical prospection to obtain the complete (or almost complete) plans of enclosures. Helmut Becker is the responsible for that survey. He is using Caesium-magnetometry.

To do his ultra-high sensitive cs-magnetometry, he is using Geometrics cs-magnetometer G-858G in the so-called duo-sensor configuration for total field measurements. The sensitivity of the magnetometer is 20 Picotesla (0.02 nT). The spacing of the 2 sensors was set to 0.5 m – with the measuring cycle of 10 Hz (10 measurements per second) the resolution was 50 x 10 cm (50 cm distance of the profiles in the 40m-grids and 10 cm samples on the profile). This is the fastest and most sensitive method for archaeological prospecting on large areas. Almost one hectare per day could be measured with this high resolution. Measuring the geomagnetic total field rather than only the gradient of the vertical component with fluxgate-gradiometry allows a much deeper penetration into the ground (major archaeological structures can be made visible to a depth of 4 to 5 meter).

Preliminary data processing is done every night directly after the fieldwork – therefore any new ideas about the continuation of the prospecting could be immediately realized.

The results have been quite remarkable, as we can see by the examples of Xancra, Perdigões or Moreiros 2.

Next week we will be starting Monte do Olival 1 and expectations are high.

0031 - Models and enclosures (1)

Walled enclosure of Zambujal (image from here). One of the classic sites in the debate of walled enclosures in Portugal.

During the seventies of the XX century, Carlos Tavares da Silva and Joaquina Soares undertook an approach that was based on localism and on a materialistic theoretical background. The emergence of Chalcolithic societies in South Portugal was seen as the consequence of labor development and production intensification, framed by a Secondary Product Revolution dynamic. This social-economic development would support segmented political structures, characterized by autonomic communities, basically equalitarian, organized at a local scale. Localism was seen as a reinforcement of social relations based on sedentary residence and in territorial contraction, generating a social, economic and political autonomous environment, according to the model of “one site / one fortification / one territory / one community”. Autarchy and competition for strategic resources would have generated a condition of “global war”, responsible for the fortification of settlements present for the first time in the archaeological record. War would export conflict and tension to inter-community relationships and preserve the internal unit of the group on an equalitarian basis. Finally, equalitarianism and political autarchy were seen as reaction to a centralist and hierarchic process, allegedly emerging in the late Neolithic. This was the theoretical background to explain the Chalcolithic walled enclosures.

Theoretical disputes apart, this model suffered from problems of scale and data. At the time, few Neolithic and Chalcolithic enclosures were known and fewer were excavated in Alentejo. It was pioneering times. Discourse was built on a reduced number of isolated sites, scarcely excavated in the majority, and quite distant from each other, extracted from their unknown settlement networks context and landscapes. A more realistic density and diversity of territorial occupation was yet to be disclosed, and the situation was propitious to localism and to interpretation centered on the site regardless its context: the site was the scale of analysis and then, by a generalization process, discourse was extending to a regional scale (Southwest Iberia). A uniform pattern of chacolithic settlements location was establish: high places, with good visual control of landscape and fine natural defense conditions.

Naturally, today this picture is no longer empirically sustainable and is also questionable theoretically. But, at the time, it was the first attempt to introduce historical materialism in the Portuguese Recent Prehistory. And, in the context of an Archaeology dominated by Cultural Historical perspectives, based on diffusion as the major mechanism to explain social change, that regarded the walled enclosures (first) as colonies and (after) as trading posts, this materialistic approach became quite refreshing at theoretical level in those days.

References:
Silva, C.T. e Soares, J. (1976-77), "Contribuição para o conhecimento dos povoados calcolíticos do Baixo Alentejo e Algarve", Setúbal Arqueológica, II-III, Setúbal, MAEDS, p.179-272.
Valera, A.C. 2009, “Cosmological bonds and settlement aggregation processes during Late Neolithic and Copper Age in South Portugal.”, Thurston, Tina L. and Salisbury, Roderick B.(eds). 2009. Reimagining Regional Analyses: The Archaeology of Spatial and Social. Dynamics. Newcastle: Cambridge Scholars Publishing.

0030 - A long way from home

Some of the imported objects and raw materials at Perdigões enclosure: “green stone” beads; recipients and idols in limestone; gold; long blades of flint; objects in ivory.

One thing in common to the large ditched enclosures, but that seems to be less significant or totally absent in the smaller ones, is the present of a lot of exogenous raw materials and artefacts. In some cases, the local of origin can be traced back to far away regions.

At Perdigões set of enclosures, and in Chalcolithic times, we have elements coming from several regions of Spain, others from Portuguese Estremadura or Alentejo´s coast and even from North Africa, like the ivory from bush elephant.

This kind of objects are absent or extremely rare in the surrounding settlements, enclosed or not, revealing that the site locally catalyzed the relations with the outside. Those relations were probably not direct, especially with the far regions, but intermediated by others. Large enclosures, then, seem to play a leading role in inter regional interaction.

In fact, several archaeometric studies (of pottery, beads, metal, ivory) in course at Perdigões are being used to built an image of those interactions, identifying potential origin places and suggesting relations whit other large enclosures, like Pijotilla and San Blás, also in the Middle Guadiana basin, but in Spain.

But because things don´t move along by themselves and because of the fact that all of those large ditched enclosures were also places where funerary practices were intensively present, we are now starting to look into the human remains (through DNA and other methods, such as teeth morphology) hopping to go further in mapping those relations.

How to value this in terms of social organization? Well, we have a couple of models available in the theoretical market. But that is food for future posts.

0029 - Porto Torrão ditched enclosure

Late Neolithic ditch (left) and Chalcolithic ditch (right)

Location: Ferreira do Alentejo municipality, Beja district, Alentejo, South Portugal)
Chronology: Late Neolithic and Chalcolithic
Bibliographic references: (Arnaud, 1993; Valera & Filipe, 2004; Valera, 2010; Valera et.al. in press)

Porto Torrão is known as a large Chalcolithic site since the eighties of the last century (Arnaud, 1983), but only in 2002 it became clear it corresponded to a complex set of ditched enclosures.

The excavations that detected the presence of ditches for the first time were conducted in a context of emergency Archaeology (Valera & Filipe, 2004), related to the building of a high voltage electricity line. The excavation of the area of one of the pillars of the line revealed two parallel ditches, separated only by eight meters (a space where some pits were also identified and excavated).

Although the ditches were close to each other, they were from different chronologies. The inner one was filled almost to the top by sediments with Late Neolithic materials and the outer one with materials from Chalcolithic, with the presence of Bell Beaker almost from the beginning of sedimentation.

The Late Neolithic ditch is 3,5 meters wide and 3 meters deep and the Chalcolithic one 5,9 meters wide and 3,4 meters deep. In the first one, some pits were identified inside the ditch, opened along the filling sediments.

More recently, again in a context of emergency Archaeology, other ditches were identified, and several necropolis of tholoi and hypogea were detected around the enclosures (Valera, 2010; Valera et al., in press). The limits and the design of the enclosures and necropolis are not yet known, but the general image points to a large complex and one of the biggest of Iberia.

Peripheral necropolis of tholoi and hypogea (a particular structure is a ditch function as an atrium of access to several the funerary chambers through passages excavated in the ditch wall. Inside the ditch, several pavements of circulation were identified). (Image published in Valera, in press,in, Michael Kunst, Roland Gauβ, Martin Bartelheim eds., Vom Erz zum Kupferartefakt. Metallurgie des 3. Jahrtausends in Zambujal und im Südwesten der Iberischen Halbinsel, DAI, Madrid.)

0028 - Walls, walls and walls

Walled enclosure of Monte do Tosco, with walls less than a meter thick (left); walled enclosure of Fraga da Pena, with walls 3 meters thick (right).

In English there are “walls”, “walls” and “walls”. In Portuguese there are “muros”, “paredes” and “muralhas”. “Muros” are short and thin walls; “paredes” are high and thin walls; “muralhas” are high and thick walls. So, whatever is the structure, in English there is no big problem with the designation walled enclosure. But in Portuguese the generalized expression is “fortified settlement” (and the structures usually designated by “muralhas”) and that raises problems.

The main problem is that the expressions “fortified settlement” and “muralhas”, on the contrary of walled enclosure, are not “neutral”: they already imply a specific intention and functionality related to defence in a context of human vs human violence. And the expressions have been traditionally used without careful, regardless available data... and theory.

In fact, and regardless everything else related to context, a wall 0,80cm thick (a “muro” or “parede”) is quite different, in a lot of aspects (labour involved, available raw material, sustainability, resistance, visual impact, meaning, function, etc.) from a wall 2,5 or 3 meters thick (a “muralha”). Just like a ditch of 1,5 meter wide and a meter deep is quite different from a ditch 10 meters wide and 5 or 6 meters deep.

So, if we want to designate this general type of enclosures, it would be better to do it with a designation not compromised with specific functions and meanings. Easyer to do it in English than in Portuguese. It is an example of the difficulties generated by the available vocabulary of a language. And we all know how language is structural to our rationalization of the world and to our knowledge production. People tend to forget that, sometimes, a name is a synthesis, an arriving point and not a starting one (or that they must run the race before reaching the goal).

0027 - Drying the enclosures

Lots of things can happen inside a ditch, like discussions between archaeologists, for instance.

The data coming out of ditches, when conveniently published, ravels that many actions took place inside, some of natural origin, most of human initiative. Along the filling layers we can detect organized depositions, pits dug in previous layers, stone structures, human burials, etc. In Portuguese enclosures, we can observe this in several sites where excavations are larger than a small section: Perdigões, Santa Vitória, Porto Torrão are some examples.

Structured deposition inside ditch 3 of Perdigões.

This is not very consistence with the idea that those ditches were built to be water canals or drains, a justification that continues to be too easily adopted in some discourses. And another inconsistence is the topography (which I already classified as very important in enclosures interpretation). Most of those enclosures are in slopes, with significant differences of altitude between the several sections of the ditches. Because of the water levelling, this topographical situation implied that water would concentrate in lower sections, living large parts of the ditches dry when the water was less, overflowing the ditches when the water was too much.

But of course water run inside ditches in rainy days. That is inherent. And when it rained hard, erosion took place, just like ditch 3 of Perdigões shows at middle depth. This could be an argument for the drainage theory. But in sites with the topography of Perdigões, an amphitheatre, the water would run rapidly to East and concentrate in the upper side of the entrances that interrupt the ditch, generating a pull and overflow the entrance. At Xancra and Monte do Olival, located in slops orientated to East and with their entrances also in the eastern parts of the enclosure, this would mean a permanent flooding of the doors and of the low parts of the enclosures. This would be very inconvenient and, mostly, would have left evidences in the strata sequence that was not yet recorded in the excavated sites.

A drain should not be interrupted and should be proportional to the draining needs. So why built drains of 7 meters wide and 3,5 meters deep? That’s a canal of the Industrial Revolution. Why built wavy drains of 2,5 meters wide and 1,5 deep to drain an area of 20m diameter at Santa Vitória or Outeiro Alto 2?

For all those reasons, water canals and reservoirs or draining structures are not very consistent primary functions to explain the building of the most part of ditched enclosures. Water flows inside them. But as intrinsic circumstance that comes along with this kind of structures. Not as an intended one for the building decision. And if there are exceptions, they must be empirically demonstrated by evidence from strata sequences inside ditches and by topography consistence and not simply assumed.

Reconstruction of the set of enclosures of Los Marroquiés Bajos (Jaén, Spain), assuming the ditches as water canals

0026 - Going public on large enclosures

It is not from Portugal (is from Jaén, Spain), but reveals one of the views develop for the Iberian large enclosures (called “macro villages”). This kind of interpretation is also assumed for Alcalar, Porto Torrão or Perdigões by some theoretical backgrounds, namely based on functionalism and historical materialism. In the last years, strong criticism has been developed, but it has not been ease to promote debate. Maybe is because of that the different approaches and the different discourses are rarely presented to the public and monolithic interpretation prevails.

0025 - Dogs, depositions and ditched enclosures

Dog skulls in Ditch 3 of Perdigões

Dog skulls in ditch 3 of Perdigões. This situation drives us to the classic problem of “is it ritual or rubbish? (Question asked by Hill, 1996). The question is, in fact, a version of the much larger problem of identifying and interpreting human intention in Archaeology (especially Prehistoric). The debate developed a concept, structured depositions, which have been used to fulfill the semantic emptiness that emerged with the criticism to the use of the modern notion of rubbish (a meaningless discard with no value and no importance).

The criticism lays in the perception that what is unsacred today and understood as waste and without value, could, in different social contexts, correspond to meaningful and symbolic actions. Therefore, we would be in presence of “structured depositions” and not chaotic and unorganized rubbish.

So, “structured depositions” emerge as a designation that “saves us” from precipitated projection of social practices anchored in modern systems of references, allowing the emergence of different intentions and different contextual social meanings.

Nevertheless, as Olsen (2000) puts it, the designation in itself doesn’t offer any explanations or interpretations regarding the nature of the depositions. Therefore, context and pattern play a decisive role in defining that nature and ultimately in distinguish rubbish from other intentional depositions.

And the context of this ditch in Perdigões is one of horizontal deposition of layers of stones, pottery shards, and faunal remains (but no other dog bones except from the skull parts). They are selected materials that are not representative of the totality of materials that circulate at the site at the time nor of dog skeleton. On the other hand, depositions of dog skulls (or heads) seem to define a practice all over Europe in the period. In Iberia, the case of Camino de las Yeseras (Liesau et al. 2008) is a reference: a ditch enclosure where in a pit several dog heads were deposited in a organized way after being cut off. In a lot of other places, the presence of dog remains corresponds only to parts of the skull (inclusively in Perdigões ditches 3 and 4): San Juan Ante Portam Latinam, Mas d’en Bixos, Pou Nou 2 and 3, Marroquiés Bajos, Picarcho, Quinta do Anjo or Alcalar 7.

And when is not the skull, are the paws in anatomical connection. In fact, the problem of structured depositions is quite linked to another one, and both should be address in the context of the same mental framework: the problem of body segmentation, shared by animal and human treatment of remains. Segmentation and valorisation of parts seems to have played an important role in the social fabrics of those societies. In fact, we are talking about segmentary societies. Segmentation is strategic and structural (Valera, 2010b). And ditch enclosures are a major context to address this problem.

(in Valera, 2010a, adapted)

References:

HILL, James D. (1996), “The identification of ritual deposits of animals: a general perspective froam a specific study of ‘special animal deposits’ from the Southern English Iron Age”, (S.Anderson e K. Boyle, Eds.) Ritual treatment of human and animal remains, Oxford, Oxbow Books, p.17-32.
HILL, James D. (2000), "Can we recognise a different european past? A constrastive archaeology of Later Prehistoric Settlements in Southern England", Interprettive Archaeology. A reader., (J. Thomas ed.), London, Leicester University Press, p.431-444.
LIESAU, C., BLASCO, C., RIOS, P., VEGA, J., MENDUIÑA, R., FRANCISCO BLASCO, J., BAENA, J., HERRERA, T., PETRI, A. e GÓMEZ, J. L. (2008), "Un espacio compartido por vivos y muertos: el poblado calcolítico de fosos de Camino de las Yeseras (San Fernando de Henares, Madrid)", Complutum, 19(1), Madrid, p:97-120.
OLSEN, Sandra L. (2000), "The secular and sacred roles of dogs at Botai, North Kazakhstan", (Crockford, S. ed.), Dogs through time: an archaeological perspective, Bar International Series, Oxford, p.71-92.
VALERA, A.C., NUNES, T. & Costa, C. (2010a), “Enterramentos de canídeos no Neolítico: a Fossa 5 de Corça 1 (Brinches, Serpa)”, Apontamentos de Arqueologia e Património, 5, Lisboa, Nia-Era, p.7-17.
VALERA, António Carlos (2010b), "Marfim no recinto calcolítico dos Perdigões (1): "Lúnukas, fragmentação e ontologia dos artefactos", Apontamentos de Arqueologia e Património, 5, Lisboa, NIA-ERA Arqueologia, p. 31-42.

0024 - Monte da Ponte walled and ditched enclosures

Geophysical image and topographical profile of Monte da Ponte (after Kalb & Hock, 1997)

Location: Évora municipality, Évora district, Alentejo, South Portugal)
Chronology: Chalcolithic
Bibliographic references: Kalb & Hock, 1997.

Monte da Ponte is one of the two chalcolithic enclosures known in Portugal that combine walled and ditched enclosures (the other is Salgada). This can be observed in the geophysical prospection image (obtained by Helmut Becker). In a small hill there are a set of several walled enclosures, some of them with bastions. In the beginning of the plain, a double circular ditched enclose the hill and its walls.

This circumstance has been used to argue in favour of a direct relationship between walled and ditched enclosures (an issue I’ll come back latter), but it is premature to assume that connection just based on a geophysical image. Facing the actual chronologies available for ditched enclosures in South Portugal, that go back to Late Neolithic (2nd half of the 4th millennium BC), we cannot assume a priori that ditches and walls are contemporaneous at Monte da Ponte. Furthermore, several occupations of a same site, separated by abandonment phases, don´t imply continuity of function and meaning, as can be seen and argued for quite a few other sites.

So, just like a lot of other complex and enduring enclosures (like Perdigões, for instance), we must put temporality in the different structures and establish their context before assume certain conclusions.

0023 - Charneca do Fratel walled enclosure

Wall of the enclosure (after Soares, 1988)

Location: Vila Velha de Rodão municipality, Castelo Branco, Beira Interior, Central Portugal)
Chronology: Late Neolithic and Chalcolithic
Bibliographic references: Soares, 1988.

Many Portuguese chalcolithic walled enclosures are known only through small archaeological interventions and several of them were never conveniently published (a traditional problem of Portuguese archaeology). This is the case of Charneca do Fratel, where an excavation was conducted in 1987/88 and published in a short notice.

That note, now easy to obtain in the net, says that, after an occupation of Late Neolithic, a Chalcolithic walled enclosure was built in a restricted sector of the previous area of occupation. The wall is two meters thick and an entrance and circular bastion were identified. It had the base made of stones and the top is thought to be made of clay. A scattered megalithic necropolis around the site is referred and the site is relatively close to one of the greatest Portuguese rock art sanctuaries in open air in the valley of a large river (Tagus, in this case) and contemporaneous of some of the engravings. The enclosure is referred as an example of South Iberia chalcolithic systems of defense.

Charneca do Fratel is at north of the south Portugal hinterland concentration of enclosures, in a region where this kind of sites is rare (for the moment). Its potential is obvious by the short description (of the site and its archaeological context) and its location makes it even more interesting. Nevertheless, research seems to have stopped, maybe because the site was considered just another fortified settlement like so many others in Lisbon Peninsula or in the Southwest and Southeast Iberia, integrating a repeated general model of social organization. I think further research should be developed, perhaps with an approach that pays particular attention to the local landscape semantics. I suspect that is an entirely new discourse that can be written about this general context.

0022 - Disclosure the enclosures

Report on Xancra´s geophysical survey published on “O Público” (click in the image to enlarge)

Although ditched enclosures are known for a long time in Europe, and in Portugal since the eighties of the XX century, the general Portuguese public ignores this kind of archaeological sites and their scientific and heritage importance. People know or heard of megalithic monuments, but they don´t have any awareness of enclosures, of their relations to megalithism, of the large sizes they may reach, of the complexity they may present, of the fascination they may have on us.
This is a problem at several levels. One of them, is that people don’t understand the need (and the costs) to preserve and study this kind of sites. They were not educated to value them, therefore they don´t value them.

So, it is the responsibility of any research project on the matter to assume its own publicity and to promote the disclosure of the produced knowledge. As someone once said, the goal of scientific knowledge is to become common sense. Only shared it gains its social relevance and be in a position to require for social value and support.

And ditched enclosures can provide us with a lot of important and attractive stories to tell about Prehistory and about ourselves. As they did in the past, they can help bringing people together around heritage value, especially in times of difficulties, where culture tends to be undervalued.

0021 - Digging at Perdigões 1

Next month I’ll be back to Perdigões, continuing the excavations in the central area (the NIA-ERA Arqueologia project and the project on funerary practices supported by FCT, where NIA-ERA has the collaboration of the Anthropology Department of University of Coimbra and the Nuclear Technological Institute).

There, we have the inner ditch from Late Neolithic (with several pits and ovens) and a possible palisade canal. As is clearly seen in the geophysics, in the area of excavation a large circular “structure” slightly cuts the inside part of the ditch. This cutting was done in Chacolithic times, and several deposits and structures are filling that circular “something”. One of those structures is a pit filled with deposits of human cremations done elsewhere. Other structure with burned human bones was detected nearby and will be excavated this year. The sequence ends in the Eastside of the surveyed area, with a large circular stone structure (not yet completely defined), apparently associated to beaker pottery and other pottery shapes that suggest a Late Chalcolitic / Early Bronze Age.

So, in the same small area (of 180m2), we have an interval of occupations of 1000 to 1500 years, with very different uses and structures, revealing how complex is the sites and how cautious we must be in the interpretation of the geophysical image. “Putting time” in those endless structures is one of the most important tasks of the next... shell we say... decades (if we have in mind the almost 20 hectares of site).

Reference:
Valera, António Carlos (2010), "Construção da temporalidade dos Perdigões: contextos neolíticos da área central", Apontamentos de Arqueologia e Património, 5, Lisboa, NIA-ERA Arqueologia, p. 19-26.

0020 - The importance of Topography

The picture presents the topographical locations of Xancra (at the top) and Monte do Oilval (at the bottom). Both are in the middle of slopes, with high ground behind. Xancra is in a smooth open slope facing east. Monte do Olival is in a more inclined one, with the hill top just in the back of the enclosure, facing northeast. The chosen topographical ground for these two enclosures is quite similar to the one selected to the cromlechs of Almendres or Vale Maria do Meio.

0019 - "Wavy ditches"

The number of known ditched enclosures in South Portugal has been increasing in the last years, being almost thirty now. Between them, several present a peculiar design that has been designated by “sinuous ditches”. This peculiar configuration didn’t raise the necessary attention to its interpretation, as a result of a functional attribution that doesn’t question the ideological foundations of architecture.

In a recent paper (Valera, in print 2010) I presented a first attempt to organize these particular designs in four basic categories according to integral or almost integral plans of ditches:

A. Sequences of regular and aggregated lobes (1. Santa Vitória; 2. Outeiro Alto 2; 3. Xancra); B. Sequences of separated regular lobes (4. Moreiros 2; 5. Águas Frias); C. Regular wavy (6. Juromenha 1; 7. Perdigões); D. Irregular wavy (8. Águas Frias; 9. Perdigões).

This morphological diversity is certainly meaningful and the traditional association to the design of walls with bastions, if arguable for some of these categories (such as the B. or even D.), is clearly unacceptable for the A. and C.. Explanations for the particular designs like the ones in Xancra, Santa Vitória or Outeiro Alto, that so far represent a specificity of the middle Portuguese Guadiana basin, need to be searched elsewhere. In the quoted paper I argued that some answers can be found in the ideological connotation of architecture, namely in its cosmological foundation. Locations, topography, astronomic orientation, landscape connections and design, all talk about architectures that are impregnated by cosmologic senses, without which these sites cannot be comprehended.

Reference:
Valera, António Carlos (in print 2010), “Fossos sinuosos na Pré-História Recente do Sul de Portugal: ensaio de análise crítica”, Actas do V Encontro de Arqueologia do SW Peninsular.

0018 - Filling ditches

Ditch 3 at Perdigões set of enclosures

One of the main questions on ditched enclosures is the nature of the filling processes of the ditches. Natural courses, usually surface erosion; human activity associated to discarded rubbish; human activity related to structured and meaningful depositions. These are the most debated origins to explain the deposits inside ditches. But, once again, theoretical debate and empirical evidence kept missing each other, resulting in axiomatic disputes.

In Perdigões enclosure, ideas are being tested. Different ones. Competing ones. Ideas that may be conciliated. Ideas that cannot.

Regarding the filling processes, the wavy ditch 3 revealed an interesting situation (Valera, 2008). A first dynamic of clear human origin, characterized by horizontal depositions of layers of stones, pottery shards and faunal remains (also with some human remains) was in course until the middle filling of the ditch. This process was dated by radiocarbon from the first half of the 3rd millennium, with equal dates from the bottom and the top of this first sequence, suggesting a relatively "rapid" filling (Valera & Silva, 2011).

Then, an episode of hydro erosion occurs inside the ditch, excavating a canal and generating sedimentation of silt layers, with little archaeological material.

Section of Ditch 3 and calibrated radiocarbon dates (two sigma)

The filling of the upper half of the ditch corresponded to a different dynamic. Structured depositions of human origin continued, but were much more restricted and of different nature. The archaeological material is now of smaller size and more disperse. Stones are rare. And the radiocarbon date for the beginning of this phase points to the middle of the millennia, statistically representing a latter moment.

The sequence was also independently detectable in the faunal analysis (Costa, in print), confirming the stratigraphic observations and radiocarbon dates.

So, we can conclude:

a)The ditch had a initial phase of filling where human horizontal and structure depositions took place, choosing particular elements: stones, pottery shards and faunal remains (with some human bones also);

b)This process, apparently rapid, stopped at middle ditch depth, and a hydro erosion process dug a small canal on the surface of the filling deposits.

c)After some time (which means the ditch half full was open for some time) a new process of filling begun, with different characteristics, where human and natural processes seem to conjugate.

d)No evidence of bank erosion was detected inside the ditch, and another one (Ditch 4) was excavated just 2,5 m distance by the inside. Radiocarbon dating shows that this opening was contemporary of the 2nd phase of the filling of Ditch 3, that definitively didn´t have an associated bank.

This process reveals that there is a decisive human intervention on the filling that, at list in the first phase, is much more important than natural processes. It also shows that the association of ditches with banks must be demonstrate and not simply presumed. Finally, it demands theoretical explanation of the nature of the human depositions, also empirically tested in honest ways and not axiomatically (or devotedly) assumed.

Why was this ditch opened and filled partially with selected materials that don´t represent a natural assemblage of the artefact universe of the communities? Why that process stopped at a certain stage and another ditch was open just a couple meters way? Why the ditch was softly waved? Why there are no evidence (on the contrary) of palisades or banks associated to it? Why are there human remains inside the ditch? Why is the ditch section profoundly asymmetric? Why...

In fact, before answer, and instead of assume, we must ask.

References:
Costa, Cláudia (in print), "Problemática do enchimento dos Fossos 3 e 4 (Sector I) dos Perdigões (Reguengos de Monsaraz) com base na análise estratigráfica dos restos faunísticos", III Jornadas do Quaternário. Evolução Paleoambiental e Povoamento no Quaternário do Ocidente Peninsular, Universidade do Minho, Braga.

Valera, António Carlos (2008), “O recinto calcolítico dos Perdigões: fossos e fossas do Sector I.”, Apontamentos de Arqueologia e Património, 3, Lisboa, NIA-ERA, p.19-27.

Valera, A. C. & Silva, A. M. (2011), “Datações de radiocarbono para os Perdigões (1): contextos com restos humanos nos Sectores I e Q”, Apontamentos de Arqueologia e Património, 7, Lisboa, NIA-ERA, p.7-14.

0017 - Walls, where have they came from?

Three or four decades ago, the origin of walled enclosures was a “heat issue” in Portugal. The battle was between two enclosed positions and a traditional "3rd way": the ones that see these architectures as a result of direct diffusion; the ones that see them as an independent local achievement, resulting of local social developments; those in the middle, that talked about local dynamics using external ideas.

Rarely, though, the debate was supported on detailed analyses of the architectures. And some details clearly seem to indicate that, responding to a general and shared European idea (just like the ditched enclosures), there is a strong link to pre-existing knowledge. This can be easily argued to the entrances of Castro de Santiago and Fraga da Pena, in the Ribeira da Muxagata, Fornos de Algodres, Central Portugal.

Castro de Santiago system of entrance.

Both entrances correspond to a short corridor that cuts through the wall and structured by vertical monoliths in each side, leaning against the stone rows of the wall. At Castro de Santiago, the two walls make a bigger corridor between them, and the South wall of the corridor also presents a revetment of vertical monoliths. These architectonic solutions, as I suggested elsewhere (Valera, 2007), seems to be directly derived from megalithic architectonic engineering, since they are very similar to solutions, in concept and layout, adopted in previous passage graves.

Fraga da Pena entrance to inner enclosure.

But the debate is, in fact, a false one, since is basically a problem of scale and of whole / part relationship. At a large scale, at an European level, there is a general trend in Europe. That trend explains the Megalithism, the circular ditched enclosures, the building of stone walls, the sharing of certain technologies, as extended phenomena. It expresses itself through local and regional specific solutions that justify both the observed similarities and particularities. But we shouldn´t regard the whole as the adding of these particular ways. On the contrary, what we regard as part should be understood as a unique, a specific, layout of the whole. Ditched or walled enclosures anywhere should be comprehended in a wider European context, not as a part of that general trend, but as a particular and local rooted expression of it. This overcomes the traditional dichotomy, and allows us to address similarity and difference in an integrated way.

0016 - Castro de Santiago walled enclosure

Double wall of inside enclosure.


Door of the outside enclosure.

Location: Fornos de Algodres municipality, Guarda district, Beira Alta, Central Portugal)
Chronology: Chalcolithic
Bibliographic references: Valera, 1997; 2007.

Excavated between 1988 and 1996, Castro de Santiago is a walled enclosure dated from Chalcolithic (first quarter of the 3rd millennium BC, by radiocarbon). Distant just 8 Kms from Fraga da Pena, and in the same valley, the site also uses a large granitic tor existent in a prominent hilltop to form two enclosures.

The inner one uses the top rocks that naturally form a “U” shape open to South. The enclosure is established by a double wall with a bastion structure built in the open side of the rock sequence. The two walls structure an entrance in “S” shape and to phases of occupation were detected inside, with huts, fire places and cobble structures.

The outside enclosures is defined by two parallel walls, one at East and the other at West, uniting rock formation at south of the inner enclosure. There is no evidence of structures and areas of sedimentation are rare and small, since the ground is basically constituted by the granitic bedrock.

The site was interpreted as a walled settlement that played a decisive role in the emergence and consolidation of a local identity during the first half of the millennia, process that was declining (through integration in a wider regional system of social relations) by the time Fraga da Pena appeared (Last quarter of the millennia).

0015 - Modular architectures ?

Has been recently suggested (Diaz-del-Rio, 2008) that some structures of Iberian chalcolithic walled enclosures may have a construction organized by modules. It is argued that the main walls (and not just re-buildings or re-enforcements) might have been built in sequences in time and not in short and continuous periods (building at once; building phase). Each module would be a specific project of a specific part of the community and related to the capacity of work and resources mobilization present at each time. The final building would be an aggregation of segmented projects, expressing the social organization of the community itself. As Iberian examples that suggest this sort of modular building Los Millares (south Spain) and Castanheiro do Vento (north Portugal) were presented .


(in Diáz-del-Rio, 2008, adapted)

In fact, this kind of situation has been also observed in ditched enclosures. In Germany, at Herxheim, the final image of a ditch seems to be the result of a sequence of elongated and overlapping pits. The same was reported to the Portuguese enclosure of Salgada, where the ditch was built in sections (see here).

In recent papers on sinuous ditches (Valera, in print) and on the Xancra’s geophysics (Valera & Becker, 2011), I analysed the image of Xancra and question if the same situation is not present, since similar modules (to the ones proposed to Castanehiro do Vento and Los Millares walls) are apparently suggested by the image.


(in Valera & Becker, 2011)

Naturally, this is not just a matter of building strategies. It has strong implications in the theoretical models we generate to these communities. If huge architectonic structures are built in smaller segments through time, requiring less labour mobilization and control, less logistics, they became accessible to smaller segmentary communities of parental bases, that don´t have a developed and strong social hierarchy. If so, we must carefully question how large constructions are, in fact, built and assume that heavy architecture can no longer be use uncritically as undisputed evidence of a highly social and political complexity.

On the other hand, it draws attention to the problem that many constructions are a result of a long process of construction and use, and that there is not an evident gap in time between the “building phase” and the “using phase”: architectures as living processes of construction.

Bibliography
DIÁZ-DEL-RIO, Pedro (2008), “El context social de las agregaciones de población durante el Calcolítico Peninsular”, ERA Arqueologia, 8, Lisboa, Era-Arqueologia / Colibri, p.128-137.
ORSCHIEDT, Jörg e HAIDLE, Miriam Noël (2006), “The LBK enclosure of Herxheim. Theatre of war or ritual centre? References from osteoarchaeological investigations”, Journal of Conflict Archaeology, 2, p.153-167.
VALERA, A.C. e BECKER, H. (2011), “Cosmologia e recintos de fossos da Pré-História Recente: resultados da prospecção geofísica em Xancra (Cuba, Beja)”, Apontamentos de Arqueologia e Património, 7, Lisboa, NIA-ERA Arqueologia, p.23-32.
VALERA, António Carlos (in print), “Fossos sinuosos na Pré-História Recente do Sul de Portugal: ensaio de análise crítica”, Actas do V Encontro de Arqueologia do SW Peninsular.

0014 - Monte de Cortes 1 ditched enclosure

Location: Serpa municipality, Beja district, Alentejo, South Portugal)
Chronology: Neolithic (?) Chalcolithic (?)
Bibliographic references: Valera et al., in print.

Monte de Cortes 1 is a small ditched enclosure that was surveyed by Era Arqueologia S.A. in the context of rescue archaeology developed in Brinches section (Serpa, Beja) of the water supply project of Edia. The water tube trench cut the enclosure in the middle and two sections of the ditch were excavated. Almost in the middle of the enclosure, a menhir was implanted and another one was recorded nearby at the surface. Some pits, previous to the menhir, were excavated, but no other contexts were found inside the enclosure (along the trench excavated).

According to the evidences, the ditch seems to be of oval or elliptical plan and of short dimensions. The in situ menhir is not at the centre, but slightly to west. The sediments inside the ditched provide few archaeological material, basically some lithics that don´t allow precise chronological determination. Therefore, sediment sampling was done by the Portuguese Nuclear Technological Institute to effect B-OSL dating.

The enclosure of Monte de Cortes 1 is surrounded by pit structures filled with sediments but without archaeological materials. 200m East, in Monte de Cortes 2, several pits were detected and excavated (those with materials suggesting Chalcolithic chronologies) and an hypogeum with human remains dated from the 3rd millennium BC was also excavated.

The site seems to be one and only but, because of the nature of the project (a linear one) and of the police of rescue archaeology (excavation strictly in the affected area), we don´t have the real notion of the spatial connections. We are, then, left to an educated guess: that we are in presence of a complex site, with several specific areas and architectures that we aren´t able to really understand with the available data.

Located in a top hill, with an open view over the local landscape, Monte de Cortes (1 and 2) seems to be an important site in the organization of local landscape, maintaining visual contact with the enclosure and necropolis area of Outeiro Alto 2. Geophysics is programmed, now in the context of research, trying to get an image that allows improvement on interpretation.

0013 - Enclosures: centers of convergence

As I was saying, our knowledge of the enclosure phenomenon in South Portugal is changing quickly. But this development is still basically unknown abroad, especially outside the Iberian Peninsula. In fact, we can say that Spain is in the same boat, if we consider the map presented above.

It is a map from the times when Perdigões was discovered. It shows that the enclosure phenomenon is of European scale, but the Iberian Peninsula is almost a desert. Well, at the time (1997), and in Portugal, lots of other walled enclosures were already known. So de map was quite outdated.

But as the numbers of enclosures (and archaeological work on the matter) were growing, especially regarding ditched enclosures, we kept seeing the same European map with a desert Iberia published again and again.

What does this signify? Basically, it represents the low level of internationalization of the Portuguese Archaeology of Recent Prehistory, despite its internal developments over the last 25 years.

In a way, we seem to be enclosed. Not in a way of some Neolithic enclosures, that were meant to aggregate, but in a very insular manner. Fortunately, things have been changing in the last years and Portugal is definitely on the path of joining the “prehistoric European community”. And enclosures are an issue that can contribute to this journey, renewing presently, not without irony, one of their main functions in the process of bringing people together.

The European maps will be progressively updated. In fact, maps like the one above don’t just represent distributions of archaeological sites. They represent much more. They talk about the past but also a lot about the present.

0012 - A new landscape

(South Portugal ditched enclosures from 1997 to 2011 - Valera & Becker, in print)

A truly revolution has been in course in the last few years in South Portugal regarding the ditched enclosures. The map on the left shows the situation in 1997, when Perdigões was first excavated after its discovery in the previous year. The map on the right shows the situation today: the number has been almost multiplied by five.

Most of the discoveries have occurred in the context of rescue archaeology, but some were the result of research projects. At the moment, and up to my knowledge, there are three long term research projects on ditched enclosures in the region: the one of Alcalar, developed by administration, and the ones of Perdigões and Archaeoastronomic Fundamentals of Ditched Enclosures Architectures developed by NIA-ERA (with other associated institutions).

There are, though, several academic works being prepared on ditched enclosures in the sequence of rescue archaeological excavation. That is the case, for example, of the large enclosure complex of Porto Torrão. Others, like Outeiro Alto 2 and Cortes, were integrated in wider research projects financed by Portuguese Science and Technology Foundation.

In fact, the last 14 years have seen a substantial change in the “archaeological landscapes” of South Portugal and, consequently, there is a whole new Prehistory to be written. There is a lot of work being done in this issue at the moment, with different theoretical approaches, so a significant development of knowledge is expected in the following years.

0011 - Outeiro Alto 2 ditched enclosure

Location: Serpa municipality, Beja district, Alentejo, South Portugal)
Chronology: Chalcolithic
Bibliographic references: Valera & Filipe,2010; Valera, in print.

It is an enclosure defined by a single ditch, presenting a design similar to those of Santa Vitória and Xancra: a wavy ditch, forming a sequence of well standardized semi-circular lobes, with an entrance orientated apparently to winter solstice.

It was identified in the context of the water distribution net of Alqueva dam. The ditch was surveyed in two areas by ERA Arqueologia S.A., and the archaeological material point to a Chalcolithic chronology.

The enclosure is at the East end of a small hill, while at the West extremity there is a possible wood henge surrounded by three Late Neolithic hypogea, and in the middle, to South West, a necropolis of pits and anthropomorphic hypogea from Bronze Age. Even in the area of the enclosure, some of the pits excavated revealed Late Neolithic contexts.

So, the enclosure is located in a hill that was developed through time as a space of social aggregation and of sacred and symbolic social practices, where the earlier was a condition for attraction and spatial organization of the later.

An example of a significant “place building” during 1,5 thousand years, showing how deeply rotted can be a sense of place and how meaning can be accumulated through time, generating the social memory of a place and landscape.

0010 - Moreiros 2 ditched (and palisade) enclosures

Location: Arronches municipality, Évora district, Alentejo, South Portugal)
Chronology: Late Neolithic / Chalcolithic (?)
Bibliographic references: Boaventura, 2007; Becker, Valera & Boaventura, in print; Valera, in print.

Moreiros 2 was identified by Rui Boaventura in a gravel quarry. In the quarry profiles, two ditches were identified and a small ditched enclosure was assumed. Contacting Rui, I had his agreement (and field cooperation) to incorporate the site in the NIA-ERA project (financed by Gulbenkian) on cosmological foundation of enclosures designs and geophysical prospection was done (the team was composed by Helmut Becker leading the geophysics, me, Rui and Nelson Cabaço).

Once again, surprise was expecting us. The site is much bigger and complex that the initial observations suggested. The enclosures go, at list, up to nine (in a provisional counting). The area enclosed is much bigger and some lines of enclosures assume configurations (adapting to the topography) that are quite rare (not to say absolutely new) in the region. Entrances are various in number and configuration. Palisades are, definitively, present in the definition of some of the enclosures.

But, at the surface of the site, almost no material was found. And this is another important result of Moreiros prospection: we have to be very carefully about deductions supported on surface findings. How many enclosures are enclosing “open sites” defined by surface findings in Alentejo?

Surprised by the size, we weren´t able to finish the geophysical survey. We plan to finish it next month, if no further surprises appear (that would be quite welcome, if I may add).

0009 - Leceia walled enclosure

Location: (Oeiras municipality, Lisboa district, Estremadura, Central Portugal)
Chronology: Late Neolithic to Late Chalcolithic
Bibliographic references: Cardoso, 1989, 1994, 1997; Soares & Cardoso, 1995.

Leceia is a well known walled enclosure, located near Lisbon, in a Tagus tributary (Barcarena stream). The site stands in the limit of a cliff and, after an open occupation during Late Neolithic (2nd half of the 4th millennium BC), a set of three walls with bastions were built in first quarter of the 3rd millennium. The walls are roughly semicircular and concentric, defining enclosures that use the cliff also as a limit. In a sense, it is the same logical use of topography that we find in the French contemporary enceintes an éperon or in some British proto historic enclosures. In Portugal, the incorporation of that specific topographical pre condition in the design of the enclosures is rare (maybe Columbeira presents the same situation in the north of Lisbon peninsula). More frequent is the use of prominent rock formations, to which walls are added forming the enclosures, as we can see at Fraga da Pena, Castro de Santiago and Castelejo in the hinterland of central Portugal, or in Penedo Lexim, in the Lisbon Peninsula.

At Leceia, after a period of functioning of the walls, it seems that they ruined and occupations continued over those ruins, till a bell beaker phase. The site has a long series of radiocarbon dates.

Interpreted as a fortified settlement of agro pastoralist communities, Leceia is one of the two Portuguese walled enclosures that present an inside funerary context with human remains (the other is Castelo Velho, in the north). In Leceia’s case, the context was interpreted as a dump.

This presence of human remains is, in fact, one of the interesting, and probably meaningful, contextual differences between walled enclosures and the large ditched enclosures, that present an inescapable direct relation to funerary practices and architectures.

0008 - Santa Vitória ditched enclosure

Image of the inside enclosure of Santa Vitória, published in Valera & Filipe, 2010, courtesy of Miguel Lago.

Location: (Campo Maior municipality, Portalegre district, Alentejo, South Portugal)
Chronology: Chalcolithic
Bibliographic references: Dias, 1996.

Santa Vitória was the first ditched enclosure identified and partially excavated in Portugal, during the eighties of the XX century. Naturally, according to the dominant paradigm of the time, it was seen as a settlement, a small fortified village, with an earth bank associated to a ditch. The strange configuration of the ditch was seen as a previous design of what would became to be known as the bastion walls (I recently developed a critique on the matter, still in print).

Reconstitution of Santa Vitória by Ippar.

No attention was given to the fact that there was no evidence of bank erosion inside the ditches. The fact that there were structures and clear deposition assemblages inside the ditches were not questioned, since the idea of settlement was also not to be question. Like Rabelais couldn’t be an atheist in the XVII century, this kind of sites couldn´t be anything else but fortified domestic settlements.

Well, nowadays “the times, they are changing”. In the context of winder and strong evidence from other Portuguese enclosures and different theoretical approach, Santa Vitoria can be reviewed. If there was an inside bank, as the reconstitution image suggests, where is the bank earth (supposedly geological material)? Not in the ditch, filled by deposits with a great number of archaeological material, stones and structures. If there was a bank, how could some pits be where they are (in the place of the presumed bank)? The design, we know now, is not unique and seems to respond to a pattern observed in other sites that strongly suggest that there is a cosmological foundation to this design (such as Xancra or Outeiro Alto 2), that have little to do with defence strategy. The apparently summer solstice orientation of the door of the inside enclosure is now being explored in the context of the NIA’s project ”Ditched Enclosures Plans and Neolithic Cosmologies: a landscape, archaeoastronomic and geophysical approach”.

Unfortunately, the publication of excavation results is minimum, which makes it harder to go into deeper discussion, namely about the depositions inside the ditches, since there is news of very well preserve contexts.

Santa Vitória, though, still has a lot of informative potential to the actual debate going on in Iberia about the social role of this kind of sites.

0007 - Human remains in ditches

Human remains in dicth 4 of Perdigões enclosure (I’m not actually refering to the persons in the image :), but to the humam bones off a hand foud in that area of the ditch)

The large enclosures of Southwest Iberia (such as Perdigões, Porto Torrão, Alcalar, Valencina de la Concepción, San Blás or Pijotilla) developed necropolis in peripheral or internal areas, with dolmens, tholoi type monuments, hypogea or pits. But another circumstance is currently and repeatedly reported: the presence of human remains in some of their Chalcolithic ditches. All of the referred present evidences of this practice, with the exception of Alcalar (until now).

Traditionally, the presence of scattered human bones, bodies or parts of bodies was interpreted as discarded rubbish. This is the way the situations in Pijotilla, Valencina or Porto Torrão were interpreted. Recently, in the publication of the first contexts documented at Perdigões (Valera & Godinho, 2010), I argued that this is an European practice and discussed some patterns that indicate intention and meaning, suggesting that this is just another practice of body manipulation and funerary management of the dead, probably articulated with other practices and other scenarios, and that at least some enclosures assumed an important role regarding those practices.

The idea of megalithism, as the main funerary expression of those communities, needs urgent revision. And some enclosures play an important role in that revision, since their traditionally assumed dichotomy settlement/graveyard is starting to be in serious crises.

But even more interesting (at least for me) is the fact that this revision will lead us to inquiries on cognition, world views and notions of the body (and of the concept of unit).

0006 - Perdigões complex of enclosures

Location: (Reguengos de Monsaraz municipality, Évora district, Alentejo, South)
Chronology: Late Neolithic to Late Chalcolithic
Bibliographic references: see here.

The site was identified in the eighties of the XX century, but only in 1996 was recognized in all its extension and architectonic complexity. This happened after a deep plough for planting a vineyard. Now, we know the site has an area around 20ha, and 3/4 is inside de Perdigões farm, a Esporão property. Today, a significant part of this context is an archaeological reserve and has been object of continuous research since 1997, coordinated by NIA-ERA Arqueologia S.A. and participated by several institutions and researchers.

Since 1996 taht we have an aerial photograph that shows several ditched enclosures. But the geophysical prospection undertook in 2009 and 2010 (by Málaga University, whith the coloboration of NIA-ERA and implemented by Helmut Becker) represented a major advance in the knowledge of the site.


(Image publish in Márquez Romero, et al. in print; Valera et. al in print)

The archaeological complex is composed by a sequence of ditches, roughly concentric. The ditches that have been already excavated present different sizes and depths. The central one dates from Late Neolithic, the middle wavy ones from the first half /middle 3rd millennium, and the outside one was still partially open when bell beaker arrived at the site (probably in middle / 2nd half of the 3rd millennium. The site seems to have lived for about 1500 years (condensed in that geophysical image) .

In the east side, the outside ditch defines a semi circular area where a necropolis of collective tombs is located. Two of those tombs were fully excavated and revelled secondary depositions of human remains and a great variety of votive artefacts. The tombs are partially excavated in the bedrock and present different compartments: a circular chamber, a small corridor and an atrium. The chamber and the atrium are coated with clay sediments and schist flagstones, while the corridor was built with small monoliths of diorite. We don’t have information about the roofs.
Although absolute dating is not yet available, the architecture and the material culture point to a Chalcolithic chronology from the first half of the 3rd millennium BC, with a probable reutilisation of Tomb 2 during the late 3rd millennium BC.

But funerary procedures were not restricted to the necropolis. In the inside enclosures, a pits area has been identified and some of the pits present human funerary primary depositions, dated from the transition from 4th to 3rd millennium. In the neighbouring wavy ditches (ditch 3 and 4) human remains were found in the filling deposits and in the central area a pit was filled with remains of human cremations dated from middle 3rd millennium. Funerary practices are, then, quite diversified and complex and seem to be present wherever we dig in the enclosure, as happen in several other European enclosures.

The amount of archaeological material and faunal remains is huge and diverse, revealing a strong interaction with other regional peninsular areas. Apart from local materials, we should highlight the presence of idols made of limestone and ivory, bell beaker pottery, copper and gold artefacts. Analysis showed that the ivory is from African provenance.

The location of Perdigões enclosure has a clear connection to cosmology. Topographically speaking, the enclosure is in an amphitheatre open to East, to the Álamo valley and its megalithic territory, with Monsaraz hill marking the horizon. The necropolis is located precisely in the eastside of the enclosure and next to it, in that same side, there was a cromlech. The doors in that side define the East quadrant, one in each side of the necropolis, and are orientated to both solstices. To North, South and West, visibility is restricted by the topographical limits of the site define when the outside double ditch were built. All architectonic organization suggests planning, intentionality and cosmological bonds.

The site has an interpretative centre in the medieval tower of Esporão farm, near Reguengos de Monsaraz and is now object of one of the most important and innovative research projects of Recent Prehistory Portuguese archaeology. An extensive list of bibliography is available (see above).

0005 - Door designs in ditched enclosures

The ditched enclosures present a significant variety of entrances, from simples ones (corresponding to a simple interruption of the ditch) to more complex ones, that can correlate ditches with wood structures.

In the wavy ditches, the extremity of the ditch can be turning inside (like Santa Vitória (7) or Xancra (2)) or outside (as in Outeiro Alto 2 (8)), depending if it was used the inside or outside curvature to make the interruption of the ditch.

Sometimes, though, the interruption is lateral in the curvature, as in Moreiros (4 and 6). In this way the entrance is not open in a straight line, but implies an also sinuous path to walk through.
This same conditioning can also be obtain by adding a semicircular small ditch or palisade in front of the entrance, like some of the doors at Perdigões (1) or Xancra (3). At Perdigões, this kind of entrance is also monumentalized by two large negative structures, defining a second, but interrupted, semicircular ditch.

These different, but at the same time quite alike, ways of designing the doors of the enclosures have some similar parallels in Europe, showing there are shared ideas relating the building of enclosures, although we can observe regional particularities.

0004 - Fraga da Pena walled enclosures

Location: (Fornos de Algodres municipality, Guarda district, Beira Alta, Central Portugal)
Chronology: Late Chalcolithic / Early Bronze Age
Bibliographic references: Valera, 1997; 2000; 2007.

The sites corresponds to a spectacular granitic tor that rises, rather strikingly and to a considerable height (750 m of altitude), near the summit of the right slope of Muxagata stream (a tributary of Mondego River). It has a magnificent view over the valley and it is a remarkable land mark.
Two small enclosures were built attached to the tor, using stone walls of 3 meters wide. Traces of human occupation were detected outside, in the top of the slope.
The site has been systematically excavated, revealing the absence of domestic occupation inside. On the contrary, the exceptional assemblage of finds (bell beakers, anthropomorphic figurine, personal ornaments, rock painting), and the rarity of other daily artefacts (such as lithic material or loom weights), suggest that the site had no residential function. Its topography, lower than the top of the slope, clearly make it defensively inefficient. In fact, it looks more like a stage.



Due to its location, Fraga da Pena would have played a significant role in the organization of local landscape over several successive historical periods (as it still does). Its occupation reflects a strategy that sought to exploit both the symbolic and communication potential of the tor. But the wall enclosures shouldn’t be regarded simply as an appending of a structure to a natural rock, but rather as a unified building, where both artificial and natural features were combined and interdependent in generating a place that serve as a stage for certain specific social practices.
Those social practices might be related to a narrow passage in the middle of the tor, connecting the interior of the first enclosure with the other side of the tor, to a natural balcony over a steep scarp. This passage is naturally (?) aligned with East – West axis, so when the sun rises behind the other slope of the valley, light comes through the passages, hitting part of the first enclosure that is in the tor’s shadow. A clear expression of a traditional Neolithic ideological use of landscape and natural elements.



It is a magnificent exemplar of the architecture of the period, combining in meaningful building natural and artificial elements, used to communicate and organize the landscape in the context of social identity fabrics.
Is part of a local archaeological route and its archaeological materials are exhibit in a local museum.