‘At its maximum size, the enclosure reaches 100m in diameter. The ditches alternate between a winding pattern and a linear pattern with some sinuous points, defining enclosures with diameters between 20m for the innermost and 100m for the outermost. They delimit areas ranging from 282m2 to 8156m2. The width of the ditches varies between 1.5m and 3m, with the estimated depth for 1.5m wide ditches being 0.5 to 1m deep and for 2 to 3m ditches 1.5 to 2m deep. The ditches have several entrances, sometimes aligned and structured differently. The structuring and location of these entrances closely link to how circulation within these enclosures was designed and experienced. The orientations of the entrances are equally varied, but the southwest direction predominates. Only a few fragments of hand pottery and hand mill sleeper beams were at the surface. The site is at the top of a hill, which is also the location of the Borralhos geodesic landmark. Seeing and being seen would be significant in this case. From the central point of the enclosure, visibility over the landscape is generally 360º in the immediate surroundings.’

Borralhos fits into the patterned ceremonial ditched enclosures in the Guadiana basin, with close parallels in the neighbouring Folha do Ouro 1 and Monte da Laje enclosures, less than 10km away. This patterning seems to define approximate dimensions replicated in different ditches and enclosures. There is a link between the defined and patterned metric and the astronomical and symbolic concepts inscribed in the enclosure design. In addition, Borralhos is an example of overlapping enclosures, a reality that reveals construction periodicity. Interestingly, most new ditches create enclosures virtually identical to the previous ones in size and design. A glaring example is the overlapping exterior ditches, in which most winding lines coincide, and only the non-overlapping sections allows us to perceive the existence of two construction periods. Such circumstance underlines three significant aspects for analysing the nature and social function of enclosures of this sort: the periodic redefining of the enclosures, implying intermittency in use/occupation; the sense of permanence and memory of the places; and finally, the importance given to communal work in their creation, explaining the opening of new ditches where there were previous ones when it would be easier to excavate their fillings.

Surface prospecting and geophysical prospecting by magnetometry.

Valera, A.C.; Pereiro, T. do (2020). O recinto de fossos pré-Histórico de Borralhos (Serpa): aproximação à sua arquitectura através da prospecção geofísica. Apontamentos de Arqueologia e Património. 14: 17-28.