The House of the Columns was entered from the southern stretch of the Cardo Maximus. It was built in the years 230-240 AD. The house was built in and around a pre-existing courtyard. All brick piers of this courtyard have been preserved: in the north-west and north-east side of courtyard D, in the north-west side of rooms F, G and H, in the back wall of room I, and in the south-east walls of rooms L and N. It may have belonged to a store building or market hall. The masonry has been dated to c. 190 AD.

Click here to open a detailed plan of the house in a new window (from Heres 1982, fig. 86).

A few treads of marble and travertine lead to vestibule A. Tufa blocks on either side of the entrance may have supported the columns of a porch. In the vestibule are the remains of a bench. It was lined with marble, as was the lower part of the walls. Originally a tripartite entrance with two marble columns led to the porticus of courtyard D. Later the two outer passages were blocked. A secondary entrance leads to corridor B, next to which is the external staircase C. Next to the entrances are two shops.

Most of the corridor around courtyard D has a polychrome mosaic of discs and lines, made of large, irregular tesserae. During later repairs many funerary inscriptions from the second and third century AD were used as pavement (most of these have been taken to the store rooms). The south-east part of the corridor was at a slightly higher level, and reached along a few marble treads. In the north-west part of the corridor is a geometric black-and-white mosaic.

In the centre of the courtyard is a nymphaeum with two semicircular niches, back to back, lined with marble. In front of the niche facing the back of the building are two small marble columns and a long basin. Near the other niche is a well, lined with marble. Around the courtyard are brick piers, between which low walls of opus vittatum were built. Two passages with marble treads remained: in the south-west and north-west side.

Hall E was at a slightly higher level, and reached along two treads. In the entrance are two marble columns. The walls were decorated with paintings. Room F could be reached through two doors with marble thresholds. In the back wall are two windows. Next to this room is a staircase that was reached from the street (Via della Caupona).

Heating pipes were found in the walls of rooms G, H, I and M, in the rear part of the building. Room I (with walls of opus vittatum) was a dining room (triclinium). In the entrance are two marble columns, on the floor is polychrome opus sectile with geometric motifs. Around the marble is a geometric black-and-white mosaic. The pattern of the mosaic indicates that reclining couches (triclinia) were placed along the back wall and side walls. Room M also had a floor of polychrome opus sectile with geometric motifs. Room R is a secondary vestibule. Along the north-west part of the courtyard is a row of small rooms, that present few interesting details.

Among the objects found in the building are a small statue of Diana and a relief with a nymph.