It stands in the upper part of Sardara, a village in the Medio Campidano area, and it gets its name from the little church nearby. The Nuragic sanctuary of Sant'Anastasia is characterized by a sacred well, known as funtana de is dolus (well of the pains), from which the spring emanates and is fed by groundwater aquifers. Thanks to a draining mechanism, you can enter it and admire its solid architecture, going right down to the bottom. Created with basalt and limestone blocks, perhaps in the Late Bronze Age, it has a circular room with a false dome roof, which you can get to via a flight of steps protected by a corridor covered with slabs in a jack arch arrangement. In the temple, of which only the well still remains, the water deities were worshipped, like in the Sanctuary of Santa Cristina (in Paulilatino), that has a similar structure but is perhaps from a later period.