This structure is in the center of Perdigões enclosures. It slightly overcomes a semicircle, presenting a large overture open to East. It has 10,5 m diameter and a central post hole. The small ditch that defines the semicircle has wedges inside, showing that posts were set along the ditch, forming a circular wall.
(Photo copyright A.C. Valera / Era Arqueologia - pits are earlier and later)
Who was inside would have the visibility limited by the structure to North, South and West, and opened to East, just like it happens with the natural theater where Perdigões is located. This structure reproduces the site visibility: to East, to an horizon limited by both solstices, being therefore a annual calendar at sunrise. This structure seems to scale down the site, but maintaining its visual relation with the local landscape.
(Image copyright A.C. Valera / Era Arqueologia)
It is dated from the middle third millennium BC, and integrates the grate monumental complexity of structures present at the center of the enclosures.