Basilica di Massenzio
This monument was built in the early 4th century (308-312 AD) by the emperor Maxentius. After his death, it was dedicated to his successor Constantine. Construction of the basilica involved demolition of what remained of the Velia. The site was not chosen by chance but was probably related to the emperor's desire (his family name was Valerius) to link up with the celebrated Valeria family of the republican age, so as to legitimize his political position. This family had a house and a tomb in the sub Veliis. A fragment of the Forma Urbis Severiana and excavations in the vicinity of the building show that the area was previously occupied by another large utilitarian complex, the Horrea piperataria, during the Flavian dynasty. The imposing basilica had three naves and measured 6500 square meters. The central nave was 37 m high and had three large cross vaults supported by eight columns in marmor proconnesium. In 1613 pope Paul V had the only surviving column moved to the square of Santa Maria Maggiore, where it still stands. The nave terminated with an apse on the western side, whereas the entrance in the original plans was on the eastern side. The nave was flanked to the north and south by two minor wings, each composed of three communicating coffered and barrel-vaulted chambers. The central chamber on the north side is the only one remaining. On the southern side of the building, no long visible, there was a colonnaded pronaos with steps linking the southern side of the basilica with the Sacra Via. The northern apse was not built until the end of the 4th century. In the western apse there was a colossal statue of Maxentius that was subsequently modified to make it resemble his successor Constantine. It was probably an acrolith. The marble parts are now displayed in the courtyard of the Palazzo dei Conservatori (Capitoline Museums) and the head alone is 2.6 m high. The basilica stands in the Praefectura Urbana area, which in Late Antiquity occupied the Velia and Carinae quarters behind it, and is thought to have had a juridical function. Indeed, the building has been interpreted as the seat of civil and criminal trials, which were probably conducted in the northern apse, managed by the praefectus urbi. A small passage in the northern wall leads from the apse to the outside, linking the basilica with the domus behind it.