This hypogeum, partly dug into the rock, is inside the 17th- century churchdedicated to Christ the Saviour in the homonymous village, an importantpilgrimage centre. Frequented from the Middle Neolithic age (4th millenniumBC), this site has been considered a sacred place bydifferent cultures over the centuries. A sacred well for water cult was dug inthe Nuragic age; in the Punic age this area was dedicated to Sid, the healinggod, and afterwards the Romans adopted the cult of Asklepius, attributinghealing powers to water. Since the 3rd- 4th century AD the hypogeum has beenused as a church. The present site dates back to the last Roman period: theplan, with several small rooms, is centred around a spring water well, set in around domed room with a skylight on the top. In front of it, an apsed room withtwo skylights keeps another spring water well and a Nuragic baethyl (sacredstone). In almost every wall, Punic, Greek, Latin and Arab inscriptions arestill visible together with paintings dating back to different periods, related topagan and Christian tradition. Not accessible to disabled people.