The private domus is one of the most important archaeological sites along the Via Appia Antica. The entire complex was established during the brief span of Massenzio's reign (306-312). 

Apart from the remains of the imperial palace, the complex includes the ruins of a circus used for private performances (for the emperor and his acquaintances), and a mausoleum dedicated to the memory of Romulus, son of Massenzio who died prematurely in 309 AD. 

Of the palace remain its large apsidal spaces of three rooms, the central one, known as the temple of Venus and Cupid, was the "aula palatina", the place where audiences and public ceremonies took place. 

Before the aula was an atrium in communication with a long portico and connecting the palace with the tribune of the circus, meant for the emperor and his family. The well preserved circus extends in an area between the Via Appia and the Via Appia Pignatelli. On the west side are the carceres from where the four-horse charriots left. 

At the centre of the track was the obelisk of Domiziano, probably coming from the Iseum Campense. In 1650 Pope Innocent X asked Bernini to put it upon the fountain of the Four Rivers in Piazza Navona. 

The sepulchre, probably meant as the Royal family tomb, is surrounded by a majestic four-sided portico, its main entrance is in the Via Appia, two minor entrances face the palace and the circus. The tomb has a circular shape and at its centre is a column with niches.