A megalithic monument measuring 9.20m in total length, it has a polygonal chamber with seven pillars measuring 4m in diameter (with some pillars cut and one recently fallen) and a corridor 4m long (3 preserved pillars) at the end of which two lateral stone alignments would form a small facade. The tumulus (dolmen) is virtually in ruins. It provided the following votive materials: arrowheads, segments of retouched blades, necklace beads, fragments of ceramic containers and several slate slabs with geometric decoration.

As part of the mobility study on human remains from the Perdigões ditched enclosure, we also analyzed teeth from individuals collected in Cebolinhos 1. Of the four individuals, three revealed levels (of strontium) compatible with the local spectrum (individuals from the Reguengos area) and one showed levels compatible with peripheral areas. These results show local individuals and others from more peripheral or distant areas buried in these dolmens, but the locals seem predominant.

Archaeological excavation by German archaeologists Vera and Georg Leisner in the mid-20th century.

Leisner, G.; Leisner, V. (1985) – Antas do Concelho de Reguengos de Monsaraz (1951). Estudos e Memórias 1. Lisboa. UNIARCH. INIC.; Valera, A. ; Žalaitė, I. ; Maurer, A.F.; Grimes, V.; Silva, A.M.; Ribeiro, S.; Santos, J.F.; Barrocas Dias, C. (2020) – Addressing human mobility in Iberian large prehistoric ditched enclosures: the case of Perdigões (South Portugal). Journal of Archaeological Sciences Reports. 30: 102264. https://doi.org/10.1016/j.jasrep.2020.102264