0288 - Visiting Fraga da Pena

A group of german archaeologists and students of Archaeology (headed by Michael Kunst and guided by me) visiting the Fraga da Pena walled enclosure in 2008.

Some took some risks to photograph a painting preserved in one of the rocks of the granitic tor.

0287 – Paper on enclosures of Coelheira 2

It has just got out the paper on the Coelhrira 2 ditched enclosures. 

Plan of the ditched enclosures of Coelheira 2.

Here is the abstract:

“The present paper presents the results of a rescue archaeological excavation done by Omniknos Company for EDIA S.A. in the context of the water supply network of Alqueva dam. In this intervention two small ditched enclosures, one possible hypogeum and several pits were identified, the majority dating from the Chalcolithic, as well as two cists dating from Bronze Age. The several features are characterized in their morphology and fillings and a typological study of pottery is presented. In the end some issues regarding the Recent Prehistory small circular enclosures (in which the two of Coelheira 2 can be integrated) that are appearing in Alentejo region are analyzed.”


The paper can be downloaded here.

0286 - Excavations at Perdigões enclosure

The pre applications for participating in 2015 Perdigões archaeological excavations promoted by ERA Arqueologia are open. The application file can be download at http://www.nia-era.org/publicacoes/doc_download/84-ficha-inscrcao-perd-2015

Information about the participation conditions and time schedules are in that file (in Portuguese. If information in English is needed please request it by mail to antoniovalera@era-arqueologia.pt).

0285 - They keep appearing

Some possible new ditched enclosures were identified in Google Earth.

Sub-circular enclosure in Mourão municipality.

One seems to correspond to a single ditch enclosure, while the other site seems to present a larger circular enclosure and nearby two more, of smaller size: one possible sinuous ditch slightly overlapped by a small double ditched circular enclosure in the west side.

Possible assemblage of enclosures at north of Beja.

This situation of proximity of different enclosures is becoming more frequent, and a paper that documents that situation through excavation is just coming out (Valera, Ramos e Castanheira, 2015). Situations that probably document the periodic use of a same area with a successive abandonment and construction of enclosures.

References

Valera, A.C., Ramos, R. e Castanehira, P. (2015), “Os recintos de fossos de Coelheira 2 (Santa Vitória, Beja)”, Apontamentos de Arqueologia e Património, 10, Lisboa, NIA-ERA, p.33-45.

0284 - Combining Google with field work

At Horta Nova 4 it was possible to excavate part of a ditch (by Era Company, for EDIA S.A.). Now, when we overlap the drawing and the (treated) Google image we can perceive the enclosure. And just 50 meters SE there is the small one also detected in the image of Bing Maps (and initially confused with the one in excavation, that is bigger).

0283 – Horta Nova 4

Recut section of the ditch.

The excavation of the ditched enclosure of Horta Nova 4 (Alvito) continues. The evidences of recuttings are several now, but not all present the same characteristics.

The site is located in a top of a smooth hill, just over the confluence of two streams. Through a satellite image we can see that it is a sub-circular enclosure, with more than one ditch. 

The smooth hill where the enclosure is located.

Two treated aerial images where another possible enclosure can be perceived just next to the fields division.

0282 – Excavating a small ditch enclosure

Today I was helping to define a recutting of the ditch sediments in a restricted area, filled with small stones, at Horta Nova 4 (excavations of Era Arqueologia SA for Edia SA.). A practice there is present in several ditched enclosures, that can only be recorded correctly when the approach is in area and not through small sections. The fact that a large trajectory of the ditch is affected helps this approach.

Some pottery sherds indicate that this recutting is from Late Neolithic.

0281 – Iberian causewayed enclosures

Middle Douro valley enclosures (taken from Delibes et al. 2014).

A relatively recent publication presents a synthesis about ditched enclosures in the middle Douro valley, in central-north Iberia. Also there the phenomena of enclosures revealed itself with great intensity in the last years.

But one of the most interesting aspects of this new set of ditched enclosures is that they are almost all causewayed enclosures, quite similar to the ones known in the rest of Europe.

This type of enclosures was not yet discovered in Portugal. Maybe in the future some may be detected in Beira Alta or Trás-os-Montes, in the areas that mark the western limits of the north Meseta. But, so far, the Portuguese enclosures are quite different and in the Guadiana basin they tend to privilege the sinuous patterns, side by side with linear layouts.

This shows us how the same general phenomena may be expressed in different ways in regions that are not that far away.  

References

G. Delibes de Castro, M. Garcia Garcia, J.Olmo Martín, J. Santiago Pardo (2014), Recintos de fosos calcolíticos del vale médio del Duero. Universidad de Valladolid.

0280 - Another one...

… found in the context of Alqueva water supply network. Here you can see how difficult it can be, sometimes, to detect a negative structure of this type: a darker spot, with some charcoals, a fragment of a Pecten maximus shell, corresponds to the filling of a ditch crossed by the trench open to receive the water tube.

It is, again, located in the Sado basin, in a peripheral zone to the concentration of ditched enclosures in Alentejo. They are slowly appearing in more western areas in the region. I have to update the enclosures map.

0279 - A new one in excavation

The new ditched enclosure, with a gate in first plan.

A new ditched enclosure is being worked by Era in Alentejo. The water supply network of Alqueva is crossing another enclosure and a segment of a ditch will be excavated soon. It is a small ditch, defining an apparently circular enclosure located in a small elevation over a stream. It is located in the western limits of the distribution of enclosures in Alentejo, where some other ditched enclosures have been recently discovered by enterprises and by aerial photos, enlarging the number of ditched enclosure known in the Sado river basin.

0278 - The importance of building.

One of the theories about the social role of enclosures, namely ditched enclosures, is the importance of the building process. Since Evens that the focus on the importance of building itself became a matter of discussion regarding the interpretation of the social role of enclosures. The general idea was that the main social role of the project was performed during the building process, rather than after. Some criticizing of this centered perspective in the building process has been done (for instance Whittle in a recent paper), but the criticism is more about the “centered” than about the “perspective”. In fact, the focus on the building process of enclosures, ditched or walled, is something to be taken into consideration in the understanding of their social role. Let me give you a contemporary example to explain this point.

You are all familiar with the Amish communities in America. And some of you are familiar with their traditions. Some of them have been displayed by the cinema or by television programs. They tend to show the importance of community work. One example is that presented by the Hollywood film (I think is called The Witness) with Harrison Ford. There is a couple that marries and the community joins up to build them a barn. 

When the barn was being build, all the community was there, working together, reinforcing there social bonds and identity, performing their traditions, communicating and perpetuating their world views. It was a social event of structural importance for the community as a whole; after being built, the barn was useful only to the married couple. So, the building process was socially and ideologically meaningful for the community and once the structure was finished it was only economically meaningful for a specific family.  This exemplifies, I think, the social importance of building.

The building processes are essential to understand the social role of enclosures. However, that doesn’t mean that we have to imagine, as for our example of the Amish barn, that we have a first construction phase of communal interest followed by a use phase of restricted interest. The long temporalities of some ditched enclosures and the evidences of continued constructions (new ditches, recutting of ditch filling, sometimes during long chronologies, like in Perdigões) show that there is not an easy separation between a period of building and a period of use.

The merit of this approach to building processes is precisely that: building is already using in social and symbolic terms. In fact, the social, ideological, economic role of building stars in the moment of its idealization and design and continues during building/using phases. A perspective that have been absent from the traditional theoretical approaches to enclosures in Portugal (and in Iberia).

0277 – A ditch for a palisade

This is how the filling of a ditch for a palisade looks like. 

A level of stones and others of clay by the interior and the dark sediment in the outside part of the ditch, where the wood must have been. And practically no archaeological materials inside. It is Coelheira 3, near Santa Vitória, Beja, South Portugal. Excavated by the company Omniknos  (for EDIA), it will be published soon in Apontamentos de Arqueologia e Património nº10, 2015.

0276 - Published

Contents

The times and timings of enclosures

Alasdair Whittle

Enclosures &burial in Middle &Late Neolithic Britain

Alex Gibson

The place of human remains anf Funerary practices in Recent Neolithic ditched and

walled enclosures in the West of France (IV-III Mill. BC)
Audrey Blanchard, Jean-Noël Guyodo, Ludovic Soler

Funerary practices and body manipulation at Neolithic and Chalcolithic Perdigões ditched

enclosures (South Portugal)
António Carlos Valera, Ana Maria Silva, Claudia Cunha, Lucy Shaw Evangelista

Skeletons in the ditch: funerary activity in ditched enclosures of Porto Torrão (Ferreira do

Alentejo, Beja)
Filipa Rodrigues

Enclosures and funerary practices: about an archaeology in search for the symbolic

dimension of social relations.
Susana Oliveira Jorge

Human Bones from Chalcolithic Walled Enclosures of Portuguese Estremadura:

The Examples of Zambujal and Leceia
Michael Kunst, João Luís Cardoso, Anna Waterman

Human sacrifices with cannibalistic practices in a pit enclosure? The extraordinary early

Neolithic site of Herxheim (Palatinate, Germany)
Andrea Zeeb-Lanz

Gendered burials at an henge-like enclosure near Magdeburg, central Germany: a tale of

revenge and ritual killing?
André Spatzier Marcus Stecher, Kurt W. Alt. François Bertemes

The Copper age ditched settlement at Conelle de Arcevia (Central Italy)

Alberto Cazzella, Giulia Recchia

Funerary practices in the ditched enclosures of Camino de las Yeseras: Ritual, Temporal

and Spatial Diversity
Patrícia Rios, Corina Liesau, Concepción Blasco

Recent Prehistory enclosures & funerary practices

José Enrique Márquez Romero, Vítor Jímenez Jaímez

0275 - Back to V.N. de São Pedro

Today I was in a conference where a new project on the mythical Portuguese site of Vila Nova de São Pedro (VNSP) was presented. As known, VNSP is a walled enclosure that, with Los Millares, gave name to an archaeological culture in the times of archaeological cultures.

The project, to be developed by the Portuguese Archaeologists Association, was presented today and aims to revalue the site in scientific terms and promote its public assessment.

One interesting aspect of the project is that it seems to incorporate some of the new theoretical perspectives and methodological approaches that have been responsible for a revolution in South Portugal regarding the enclosures phenomena.

In my own words, I would say that this was urgently needed in the approaches to enclosures in Portuguese Estremadura. Based in the new data and new theoretical approaches that have been developed in south Portugal, new insights may be developed regarding walled enclosures in the region and in the re-reading of old texts about old excavations.

In this path, it seems that, in old reports, descriptions of previous ditches to the walled architectures, possibly opened to be rapidly filled with symbolic depositions, are now “emerging” due to the new awareness. The possibility of ditched structures previous to stone walls in VNSP is now on the table, just by reading old texts with “new eyes”.

The approach to Estremadura walled enclosures was needing a refreshment in the scientific enquiries. That was obvious for some time now. So I sincerely hope that this new project develops the adequate inquiry, builds a solid theoretical background and manage to obtain the adequate resources to bring VNSP back to the stage, to actually contribute to the debate on the passionate phenomena of recent prehistory enclosures.

0274 - Cremation contexts of Perdigões enclosure

Data and problems raised by the contexts with remains of human cremations will be presented next December, 15, in Lisbon (Sociedade de Geografia).

0273 - Conference in Kiel

(Drwaing by Guida Casela)

Next Monday I will be in Kiel (Germany) to participate in a master with a conference about portuguese ditched enclosures.

Here is the abstract:

The research of ditched enclosures in the Late Neolithic and Chalcolithic is a relatively recent development in Portuguese Recent Prehistory. In the last two decades a significant number of these complex sites were reveled, showing different architectures, topographical locations and dimensions. Recent research started to demonstrate the importance of these enclosures to the construction of Neolithic meaningful landscapes.

In this lecture a synthesis of the available data on chronology, temporality, architecture and design, dimensions, landscape relations and social practices that took place in the enclosures (with particular emphases in funerary ones) will be presented, and the possible social roles of these places will be discussed in the light of a large scale phenomenon.

The presentation will focus particularly in the hinterland of the province of Alentejo, South Portugal. 

0272 – Paper on Coelheira 2

These are images of one of the two “twin” (?) enclosures of Coelheira 2 (Beja district). 

The site was partially excavated by Omniknos company (field direction of Rui Ramos) in the context of mitigating Archaeology. The data is now under study and a publication will be out soon. This is a very interesting site, with some new and specific characteristics, that deserved a more thoughtful approach by those that define what is “mitigating” negative impacts in archaeological sites.

0271 - Bela Vista 5 monography

It is edited the nº2 of ERA MONOGRÁFICA dedicated to the cerimonial enclosure of Bela Vista 5 (Beja, South Portugal).

Free download here

0270 - Trade or gift?

In Iberian large ditched enclosures one of the main patterns is the presence of exogenous materials that reveal that those sites were integrated in large trade networks. Ivory, cinnabar, variscite, amber, shells, some specific potteries, etc. These raw materials or objects made of them are present in those large enclosures in regions where they do not exist.

The questions are: is this evidence of just trade? Or is it evidence of something else? For instance, of the social importance of gift. It is possible that many of these ditched enclosures were stages where potlatch type ceremonies might have been performed and the exchange of rare exotic objects as gifts might have had a significant social role.

These are paths for research in Iberian (and therefore Portuguese) ditched enclosures. For that, theoretical research should be done on how can we empirically demonstrate the presence of gift procedures in the archaeological record (yes, empiricism depends on theory).

0269 – Processes of ditch filling

A paper about the processes of filling of the Late Neolithic ditches of Perdigões enclosures will be presented by the end of the month at the VIII Iberian Southwest Archaeology meeting.

Late Neolithic ditches (yellow) in the central area of Perdigões.

The goal is to confront theoretical interpretations in dispute regarding the nature of these type of contexts with empirical data, arguing that the processes of filling and what we find inside ditches are important criteria to the interpretation of functionalities. It seems obvious, and yet still needs to be stressed. 

Bottom depositon in Ditch 12.

0268 – Transition moments

Transition is always a moment celebrated by cultures (and not just human cultures). Transition between life and death, between childhood and adult life, between seasons, between day and night, etc. All generate particular culture behaviors, rituals, prescriptions.

Even architecture responds to these moments of transition. That is the case of many ditched enclosures by having their gates orientated to important sun annual events, such as solstices and equinoxes. In this case, we have a drawing of the landscape perspective of the sunset at the equinoxes, seen through the western gate of Bela Vista 5 enclosure (Beja, South Portugal).

0267 – Towers and huts

Late central towers at Porto das Carretas (left); stone huts at Mercador (up right); late central stone hut at Monte do Tosco 1 (down right). See how dimensions are quite similar.

            There are some Portuguese walled enclosures that, according to their excavators, present central towers in the latest phases when the wall are no longer functioning and enclosing. That is the case of Monte da Tumba, S. Pedro or Porto das Carretas. In general, these structures just present some rows of stones, are circular and tend to date from the Late Chalcolithic (some associated to Bell Beaker).

            However, it is never clearly explained why they are interpreted as towers. In fact, similar structures, with the same width and high and with identical diameters, are interpreted as huts. That is the case of the two huts of Mercador. They have the same dimensions of the so called towers of Porto das Carretas, they are from the same general period as the later, they dist just 1,5kms and they even are united by a short wall like the structures at Porto das Carretas. So structurally, how can we distinguish the base of a stone hut from the base of a stone tower, when we do not have enough information to estimate the vertical development of the structure?

            The larger hut at Mercador has a central post hole. But a two floors tower would probably have one also. And not all structures considered huts present internal post holes. At Mercador or Monte do Tosco, huts present internal fire places and areas of storage. But couldn’t towers present them also. During the Late Chalcolithic, what could be inside a hut that couldn´t be inside a tower? So, internal context also doesn’t help much in establishing a difference.

            So, in what bases do we call towers to the late central structures in Porto das Carretas, S. Pedro or Monte da Tumba? Or are they really stone huts, associated to late occupations of these sites? We need criteria and solid evidence to name these structures.

0266 - Coming soon

0265 – The ephemeral history of walled enclosures

Plans of S. Pedro (Mataloto, 2010) and Porto das Carretas (Soares e Silva, 2010). References in the page of W.E. Bibliography.

I recently defended (Valera, 2014) that during the second half of the 3rd millennium BC walled enclosures are no longer built in Alentejo. Some may still be in use during the third quarter, others are abandoned, others present bell beaker reoccupations, but there is no record of the building of new wall enclosures.

According the actual available data, in the long duration of the building of enclosures and monumental architectures in South Portugal, the construction of walled enclosures are a late adding (first centuries of the 3rd millennium) and seem to have a relatively ephemeral life, with the activity of building walls ending by the middle of the millennium.

References:

Valera, A.C. (2014), “Continuidades e descontinuidades entre o 3º e a primeira metade do 2º milénio a.n.e. no Sul de Portugal: alguns apontamentos em tempos de acelerada mudança.”, Antrope, 1, Tomar, IPT, p. 298-316.

0264 – Maybe an actual issue in many dimensions

I have just been contacted by a colleague from Ukraine. The reason was the similarity between some ditched enclosures. 

That the approach to Iberian ditched enclosures has to have a scale of continental level is something that I and other Iberian researches have been stressing. There is a general phenomenon that have regional expressions, dynamics and particularities. Here, we are working our own regional expressions and dynamics, but it is useful not to forget the problems of structural larger scale.

The familiar image of this Ukrainian enclosure is not just another parallel. Is a reminder that we are dealing with a large scale social dynamic (in the broader sense of “social”).

 Generalka 2. Plan kindly provided by Oles Tubolsev

0263 - Portuguese enclosures in world congress

After the session organized by NIA-ERA in 2006 in the UISPP congress in Lisbon, where the “Idea of Enclosure” was debated, after the international congress held at Gulbenkian (Lisbon) in 2012, organized again by NIA-ERA and dedicated to discuss the relations between enclosures and funerary practices, Portuguese ditched and wall enclosures are again in a international stage: they will be presented and debated tomorrow in the UISPP congress, held in Burgos, Spain.

The following sessions are to be highlighted:

A25d - Monumentality and territory: relationship between enclosures and necropolis in the European Neolithic.

B44 - Within ditches and walls. Settlements, fortifications, enclosures, monuments, villages

and farms in the third Millennium BCE.

0262 – Salvada measures

Salvada is one of the Portuguese big ditched enclosures. Well, by present standards of Iberian Enclosures, we should say it is a middle sized enclosure. It has about 500m diameter and about 17.5 ha.

I provide now some new measures, regarding the outside ditches. Based on aerial images, it is possible to say that the distance between the two outside ditches is around 10m (quite similar to Perdigões, where the outside ditches are 11m apart).

The inside ditch at Salvada is a sinuous one, with patterned semicircular lobules, measuring about 10m wide each one, amazingly similar to the general measures of the lobules at Xancra enclosure.

Naturally these measures have some incertitude due to the fact that they were taken in the blurred aerial images. But the proximity to the Pergigões distance of the outside ditches and the similarities with the measures of Xancra lobules are interesting. I will explore more this path.

0261 – Portuguese enclosures go to Germany

Next November, and by invitation, I will be lecturing in the University of Kiel, Germany, in a biweekly master dedicated to historical landscapes.

There, the developments of the ditched enclosures research in Portugal during the last two decades will be presented, and the social roles of these sites will be discussed.

The main goal is to contribute to the international display of the Portuguese recent research on ditched enclosures, a work that has been rising considerable curiosity and interest in several European countries where this general phenomena is present and studied for a long time now.

This is a task that I have been developing in the context of my work at the research department (NIA) of Era Arqueologia Company.

0260 - Gate at Perdigões ditch 10

This is a projection of the drawing of the gate detected in ditch10 at Perdigões. It is a large gate (about 7 meters wide) and it is located in the west side of the enclosure. Due to the topography of the natural theater where the site is, a person entering in the enclosure through this gate would have in front, as a stage, the megalithic landscape of Reguengos de Monsaraz, with the hill of Monsaraz in the horizon. But if that person was going in the opposite direction, and at the late afternoon, then the horizon would be the limits of the natural basin and he would have the setting sun in his eyes.

At Perdigões, gates are more than simple passages. Their location generates meaningful perspectives of the landscape. 

0259 - Interesting...

... finding regarding the figurines from Perdigões enclosure here.

0258 – Return with a new one

I’ve been away from this space for several weeks, mainly because I was in excavations in the ditched enclosure of Perdigões. It is now time to come back and recover the usual posting regularity. And nothing better than coming back with a new discovery in Alentejo: another small circular ditched enclosure in Beja district. Courtesy of Tiago do Pereiro.

0257 – Long term ideas expressed in Perdigões architecture: a goal for 2014 campaign.

Next Monday the 2014 campaign of excavations (the 15^th of the research program) will start at Perdigões enclosure. You will be able to follow the results here.

One of the goals of this year is to start sampling ditch 10, in an area where it seems to be a gate (in the geophysics image). If it is confirmed, it should be noticed that the gate would be aligned with gate 4 in the outside enclosures. And that is very interesting for the interpretation of the architectonic dynamics in Perdigões, namely to the issue of how some previous structures conditioned the later and to the idea that, in Perdigões, there are long term ideological conditions that are imbedded in the architecture of enclosures. Something that I have been pointing out for some time now. 

0256 - The origin of walled enclosures in Alentejo

Radiocarbon dates for walled enclosures in Alentejo

For some time the origin of walled enclosures in Alentejo was thought to have occurred in the second half of the 4th millennium BC. The radiocarbon dates from two sites seem to indicate so: the chronologies from Monte da Tumba (Silva e Sores, 1987) and São Brás (Parreira, 1983).

These old dates, thought, were obtained over charcoal and they have a large standard deviation and in face of another set of dates, some of them more recent and obtained over bone, the actual image on the issue has changed.

The dates from Escoural (Gomes, 1991) walled enclosure, from Monte Novo dos Albardeiros (Gonçalves, 1988/89) and more recently from São Pedro (Mataloto, 2010) and  Porto das Carretas (Soares e Silva, 2010) indicate that these architectures emerge in the beginning of the 3rd millennium BC, namely after 2900 BC. This is coincident with the limit that radiocarbon establishes between Late Neolithic and Chalcolithic contexts in ditched enclosures (Valera, 2013a). Furthermore, the chronology available for the Late Neolithic hypogea of Sobreira de Cima (Valera, 2013b) and for the funerary context of Gruta do Escoural (Araújo e Lejeune, 1995), clearly in the second half of the 4th, corroborates this argument. In fact, it is not credible that these funerary contexts, with their unquestionable Neolithic assemblages, could be contemporaneous of early Chalcolithic walled enclosures, with a completely different material assemblage and just a few miles away.

The old dates should be abandoned in the debate of the origin of the walled enclosures in Alentejo. They clearly are a phenomena of the beginning of the 3rd millennium BC. And an ephemeral one, since the majority of the dated ones seem to end around the middle of the millennium (the recent dates of Porto das Carretas correspond to a phase where the enclosure was already deactivated and the one from M.N. dos Albardeiros from a possible reutilization). Several are reoccupied in Beaker times, but not as enclosures, like Porto das Carretas or Mnte do Tosco (Valera, 2000).

In the long time span of ditched enclosures, walled enclosures could have been just a temporary adding to the architectures of the societies that lived in the region.

This is an argument that I am developing in a paper that is almost ready.

0255 - Evaluating the effort 3

Prehistoric ditch in Avebury (UK)

Evaluating the effort of digging ditches and of building ditched enclosures is not just a question of measure the amount of rock and earth excavated and moved. That is just part of the equation. Other important parts are the number of people involved and the duration of the building activities. As noticed by me and others, great building enterprises are available to small communities if they are done by stages in time and if they can congregate the will of the community. And it is in that will that I want to focus today.

Functionalist approaches naturally focus on function. No problem with that. The thing is that they focus in the function of the structure once it is built, and pay no attention to the function of the building process, which is an important social one.

For some decades now, some have argued for the need to focus on the social importance of the act of building. An act that goes much further than the pretended function of the feature itself. We have innumerous examples from all over the world and from different historical periods. Let me just give one example that I think is known to everyone: when Amish are reunited to build a barn for one member of the community, they are not simply building a barn to perform the function of storing the crops. They are doing something that touches deeply the identity of the community and reinforces their world vision, their social, political and religious bonds. As Marcel Mauss reminds us in his essay about the gift in polonaise societies, this facts that we study (in this case building activities) “are all total social facts, for they put in movement the totality of the society and its institutions or just an enormous number of those institutions, in particular when interactions were related to individuals. All these phenomena are simultaneously juridical, economical, religious, esthetical, morphological, etc.”

That is why some decades ago Evens argued that the process of building an enclosure had its main focus on the build process. For a functionalist mind focus on the subsequent utility of the thing, this might be hard to understand. But in many societies, inclusive in ours, many creations culminates in the very act of creation. Christ, we are leaving the times of the ephemeral.

And yet, it seems so difficult for some, today, to conceive that huge building enterprises might have had their basic motivations in the very act of building, in an ephemeral use and in the subsequent condemnation and in its social and ideological implications.

To evaluate the effort of building ditched enclosures in Prehistory it is important to go further than impressive metrics and politics of coercion.

0254 – Knowing what method to choose

At Perdigões two methods of geophysics were tested. First georadar. Slower and needing a considerable cleaned soil (for the radar runs a few inches over the surface), this method was totally disappointing. 

Georadar image of the center of Perdigões enclosures

On the contrary, magnetometry, not just is faster in the measurements, but provided excellent results. In Perdigões, but also in Xancra, Moreiros 2, Monte do Olival 1, Luz 20, Montoito, Monte da Contenda, images that you can see all through this blog. Or you can search in the net for tens of European examples.

Image of the same area done by magnetometry 

For negative structures, like pits and ditches, magnetometry is the method that provides best results. Of course the quality depends of several circumstances (like the bedrock or the proximity of highly magnetic material) that need to be taken into consideration.  But the results leave no doubt.

0253 – Evaluating the effort 2

At Perdigões we have recorded 12 ditches. Seven of them were already surveyed in a section. Of course that we do not know if the dimensions of those sections “speak” for the entire perimeter of the ditches. We have evidence from other sites that a ditch volume and shape may change a lot along its perimeter. And Perdigões is not an exception. Ditch 12, the only one surveyed in two different areas, has a different shape and a different filling in survey 1 of Sector Q and in survey 2 of the same sector.

That shows us that we cannot generalize to a whole ditch what we observe in one section. But does not imply that, in general terms, we cannot try to approach the general picture.

For instance, Dicth 1 at Perdigões is a long one: it has a perimeter of almost 1,5 km. It was surveyed in a section near Gate 1, first by the ERA team and in the last few years by University of Málaga team (that is collaboration in the General Program of Research of Perdigões). It showed a “V” shape, with about 3 m deep and 7 to 9 meters wide. It allow us to calculate a volume for a one meter section: 9.61 m3. Multiplying this volume by the perimeter we get a volume of 14232 m3 and using the pattern wait of a m3 of diorite (around 2600 Kg) we have 37 000 tons of rock extracted, just for Ditch 1.

This can gives us an idea of the amount of work involved in Perdigões through its living time. And more interesting: once again, where is that amount of bedrock?

Ah! And do not forget that we have evidences of practices of re-cutting of some ditches after their first filling process. And that enlarges the amount of work that we can calculate to the recorded structures.

These big enclosures were huge public enterprises.

0252 - Evaluating the effort 1

Outeiro Alto 2 is a small ditched enclosure. It has just one ditch with a perimeter of 101m. If the size of the ditch is regular (as the two opposite surveys suggest) it will have a volume of 254 m3, corresponding to 406 tons of extracted rock (1600kg per 1m3, as average for limestone rock). That rock is not in the site: not outside the ditch and not inside the ditch (as it would be expected if there was a bank built with the extracted material). This is a common situation in Portuguese Ditched Enclosures, big or small.

0251 – The chronology of ditched enclosures

According to available data, the building of ditched enclosures in Portugal ended in the last centuries of the 3rd millennium BC. Some show signs of occasional occupations during Bronze Age. But there is no evidence of ditches being built after 2000 BC until the Late Bronze Age, at least in the area of the great concentration of Late Neolithic and Chalcolithic enclosures: the Alentejo´s hinterland.

Radiocarbon dates for portuguese prehistoric ditched enclosures

The big question is why? Why such important architectures disappear abruptly? Especially after some of them reach sizes and complexities never reached before.

My answer, published in several papers, is that the reason for the disappearing of ditched enclosures has to do with the disappearance of the reasons for their construction. And that reason was an ideological, cosmological, one. They appeared to respond to a Neolithic world view and related social practices. When that cosmological perception was ending, they reach their biggest sizes and complexity, just like in the end of Middle Ages, feudal societies produced their most emblematic and exuberant architectures: the cathedrals. And then they abruptly disappeared. A significant change occurred by the end of the 3rd millennium beginning of the 2nd. Building ditched enclosures made no more sense. Not because communities stoped having defense problems or draining problems (functionalities that for some are the reasons for these architectures). But because the ideological frame that justified the development of these architectures was changed. The disappearance of ditched enclosures (and of megalithic traditions) in South Portugal marks the end of the Neolithic cosmologies. And a new world view would developed through the Bronze Age, naturally with some detectable continuities, but clearly revealing a new social organization and new perceptions of the world and of human ontologies. Ditched enclosures like the Neolithic and Chalcolithic ones had no place in this new world.