Dolmens are collective funeral monuments that correspond, generally, to the second phase of regional megalithism; they were built for the most part at the end of the Neolithic, less than six thousand years ago. The funeral megalithic monuments that came before dolmens were formally similar although smaller in size and without a corridor and corresponded to individual burials.

The Anta Grande do Zambujeiro, one of the largest megalithic monuments on the Iberian Peninsula, was discovered in 1964 by the archaeologist Henrique Leonor Pina. The grave goods discovered there are deposited in the Évora Museum together with a rich collection of prehistoric artefacts from other passage graves in the region (Anta dos Cabacinhitos, Anta da Loba and Anta da Mitra).

The monument was built between the beginning of the 4^th and the middle of the 3^rd millennia BC, between the Late Neolithic and the Chalcolithic periods, when the economy of the hunter-gatherers was undergoing changes with the flourishing of agriculture and animal husbandry as well as the perfecting of new technologies, with work in polished stone and with metal founding.

It is a large megalithic monument (a dolmen) comprising a funeral chamber made up of seven slabs of stone (props) and a passage about twelve metres long giving access to it. At the time of its discovery it formed an artificial mound surrounded by a structure of stones and earth more than 50 metres in diameter. On the surface, the only thing visible was the massive slab for covering the chamber (the capstone), which today lies broken nearby.Here was practised the funerary ritual of collective inhumation, generally accompanied by deposits of artefacts which had acquired a magical-religious significance pertaining to death. There are pottery vessels, arrowheads, blades, axes and adzes which, although they had a utilitarian meaning in the daily lives of these communities, show no signs of use, as well as being realised in smaller size and including decorative effects. Also found were numerous objects that were exclusively symbolic, such as schist plaques and crooks, the first designed to be placed over the body of the dead person and the second, a mark of power, occurring more rarely. Among the grave goods, a very rare example of prehistoric jewellery is outstanding, a gold plaque with geometric decoration, common on schist plaques and the decoration on the pottery of this period.

Besides being a place for the celebration of religious rituals, the Anta Grande do Zambujeiro presents itself as a mark on the landscape which gives a material focus to the relationship between a territory belonging to a group and a permanent contact with ancestors that is so much more imposing – and important – when compared to the habitations built in an open area, seasonal in character, expressing little in the material witnesses they present.
The Anta Grande do Zambujeiro, classified as a National Monument by Decreto 516/71 DG 274 of 22-11-1974, is situated near Valverde (Nossa Senhora da Tourega, Évora). It is temporarily closed to the public.