The warm bath is where sweat and dirt is washed and scraped off.
The room is elongated with apses at the ends. It was a heated room, by means of two external ovens, the praefurnia. The suspensurae, the columns now visible, held the elevated floor and allowed hot air from the praefurnia to flow freely below.
The mosaics in the tepidarium has been damaged a lot with the collapse of the major parts of the floor. Only a few fragments remain, but it appear to have shown athletic scenes. Various body parts can be recognised, mostly legs, but also some persons with shields and a protective armour on one arm.