There are several crossings of ditches, which indicate different construction moments and overlapping enclosures. We have a visible set of ditches that establish larger enclosures, with oval configurations, and another set of enclosures further inside and off-centre regarding the first, with a circular and concentric tendency, similar to that found in Monte da Contenda (North route). It is one of the best examples of construction periodicity in these areas and representative of the intermittent nature of the occupations. Along with the ditches are numerous pits (more than a hundred) and some circular structures (possible huts or small enclosures) in the northern part. Abundant materials appear at the surface, collected in various prospecting works, such as ceramic fragments (some of them decorated), polished stone axes and adzes, arrowheads, blades, spoons, loom weights, weavers, anthropomorphic ceramic figurines, a bowl with an incised drawing of a human body, idols in schist and limestone, slate slabs with geometric decoration, crucibles and copper objects, as well as human remains. These materials allow us to associate the site with the Late Neolithic and Chalcolithic, between the last quarter of the 4th and the middle of the 3rd millennium BC, revealing the existence of a wide variety of activities and a significant ceremonial trait, with several elements that refer to the sacred, as well as the presence of funerary contexts and the handling of human remains. Its location is on a south-facing slope, showing no defensive concerns and visibility over the landscape is limited to the south.

Two structures deserve particular attention. One appears to have a large circular chamber with an access corridor, with iron slag collected from the surface, so it may not be from the prehistoric period. The other seems to correspond to a corridor, about 50 meters long and with an entrance with a small facade, possibly made of stone, which leads to the central circular enclosure, facing East (75º). It is an unprecedented case in peninsular ditched enclosures. Due to the recorded magnetism, the corridor appears to consist of stone. If so (only archaeological excavations will confirm it), it resembles the architectural principles of megalithism, reinforcing that, despite their discrepancies, ditched enclosures and megalithism share cosmological principles expressed in their architectures.

Surface prospecting and geophysical prospecting using magnetometry.

Soares, et al. (2022), São Brás 3. Um sítio de planície do Neolítico e Calcolítico nos arredores de Serpa (Baixo Alentejo). Comunicação apresentada ao XII Encuentro de Arqueología del Suroeste Peninsular, Aljaraque, 20-23 Octubre 2022.