Salgada (Rio de Moinhos, Borba) is one of the few chalcolithic settlements, in Portugal, where recent excavations have revealed a ditch cut through the bedrock. The structure has presumably enclosed the whole settlement (or a part of it) and was probably conected with a strong wall (2, 50 m large) which has been found some 20 m far from the current excavation trench; in this one, the wall seems to have been completly eroded out. The settlement, as defined from the surface scatters, is likely to have ocupied an area with around 3 ha.
This trench allowed us to observe part of a poligonal ditch, with an entrance, facing eastwards, some 5 m large, where, in a late moment, it has been cut a narrow channel, connecting both ends of the ditch. The ditch itself has been cut in independent portions, recalling the british causewayed enclosures, though in this case, those parts are connected in sequence.