Clearly visible inside the monastery of the Clarisse are some impressive ruins of public thermal baths. They consist of a room, the calidarium, with a vaulted covering, measuring more than 30 square meters with a maximum height of 9 meters. It is intact but some areas of the ceiling have been restored. The walls are made of naked opus testaceum and there are some openings in the wall which are terracotta vent ducts for heated air. The walls are covered only with plaster and the original mosaic stones are no longer visible. The sidewalls, however, are more or less complete as is a chair built against the wall. No significant remains of the frigidarium and tepidarium are left.
This is one of two thermal baths in town, known for the health and sacredness of its waters. The other one, Santureggio, is a center for water therapies and is located near a spring outside the walls, in the southwestern part of the city.