Discovered by accident in 1973, excavations uncovered important artifacts, including numerous tombs, oil lamps, belt fibulas and some jewelry. The site is best known for its polychrome mosaic, the largest in surface area found in Sardinia, which scholars say was the floor of a 4th-century AD church, presumably built on a 2nd-century AD bath site. The central part of the mosaic is later, inserted perhaps following a renovation in the 6th century AD. The large mosaic hall (about 160 sq. m.) features symbols referable to Christianity in the central area, such as Kantharos, the vase that contained wine, the ear of millet and the vine or ivy leaf, highlighted by a frame with polychrome ornamental motifs. The area has been interpreted as a mansio, that is, a rest station on the road from Cagliari to Sulci (Sant’Antioco). It is speculated that the church of San Cromazio was the parish church of Itzo, an early medieval village that arose in Bidda Itzu.
