The so-called Basilica is a hall (c. 14.50 x 11.30), that could be accessed from the Decumanus Maximus. It was excavated during the First World War by Paribeni. The walls are of Hadrianic opus latericium.
The hall is divided in two naves by brick piers. The left nave is wider and has an apsidal wall of opus mixtum at the north end (w. 3.60, d. 1.70). To the left of this nave is a corridor, with a door in the north wall. There is a door at the north end of the right nave as well. Several modifications took place: entrances in the east wall of the right nave were blocked (opus latericium); a few brick piers were added in the north part of the left nave; the entrance of the left nave from the Decumanus (6.35 m. wide) was narrowed and decorated with a porch; in the left nave a rectangular masonry basin was added. The north wall with the apse and the additional piers has been dated to the second half of the third century. The narrowing of the main entrance and the latericium of the east wall have been dated to the years 350-375 AD.
To the north-east are two rooms, a latrine and a staircase, to the north-west is the Aula del Buon Pastore (I,II,4). Here a marble plaque (0.19 x 0.25 m.) was found in 1951. It was erected during the reign of Gordianus III (238-244 AD) by the lenuncularii traiectus Luculli, a small ferry-service on the Tiber:
"To the imperator Caesar Marcus Antonius Gordianus, Pious and Lucky, Augustus, the guild at Lucullus' Crossing".
The "Basilica" may well have been the seat of this guild. It has been suggested that the Caseggiato del Termopolio (I,II,5), to the north and west, was owned by this guild.
From the Basilica comes a marble slab with the inscription:
Plan of the Basilica.
After SO I.