To the south-west and south-east of the theatre are two semicircular fountain-houses or nymphaea, facing the Decumanus Maximus. They were probably built during the reign of Domitian (81-96 AD) and rebuilt at the end of the second or in the early third century AD. Marble columns were later added to the eastern and perhaps western fountain.

Unfortunately not much has been preserved of the fountains. The masonry behind the hemicycles probably carried a niche from which water reached the basin in front, through lead pipes. Two marble gargoyles in the form of ship's sterns may belong to the fountains. In each basin are two bases, presumably for statues. On top of the eastern fountain are the remains of the Christian chapel II,VII,1.