This nymphaeum is in the eastern part of the area in front of the Four Small Temples (II,VIII,2). It is directly to the north of the Shrine of Jupiter (II,VIII,4).

The walls of the nymphaeum have been preserved to approximately half their original height. Around a more or less square room (5.15 x 5.35) are three semicircular niches. Originally the niches reached to the floor. The lower part was later filled in. In front of the niche in the back wall is a small podium. Two marble consoles supported little columns. In this niche a hole for a lead water-pipe was seen in 1913 - it has now disappeared.

The floor of the room was covered with marble. The walls were decorated with an alabaster and marble socle. Above was painted plaster with stucco reliefs, which also decorated the ceiling. The room is reached through a small vestibule with low benches. The outer wall was painted red.

The first phase of the nymphaeum has been dated to the reign of Hadrian (opus mixtum).