This privately owned facility (1st cent. BC – 1st cent. AD) is built on an artificial terrace facing the sea, just outside the walls: eminent due to its scenic position, it was repeatedly pillaged over the centuries. On the ground floor are the sumptuously decorated bathing rooms, including the warm indoor pool, and the small cold pool with painted walls ending in a niche: a waterfall bubbled up from an imitation cave, decorated with a mosaic depicting Mars and cherubs. The frigidarium (cold room) has a decoration of stucco squares. There is a curious ‘fourth style’ fresco in the changing room: 16 panels show erotic scenes, including one with two women unique in Roman painting.