Triumphal arch found buried under Circus Maximus.

Archaeologists working in Rome's Circus Maximus have unearthed large marble remains belonging to a lesser-known Arch of Titus dating to 81 AD, the year in which the emperor died.

The triumphal arch was originally 17m wide and 15m deep, with four 10m-high columns, and was designed to form a majestic entrance to the Circus Maximus.

A better-known Arch of Titus can be found in the Roman Forum. It was built in 82 AD by the emperor Domitian, a year after the death of his older brother Titus.

Over the ensuing centuries the Circus Maximus monument fell into disrepair and its stone was used for building materials, while its foundations sank below ground. Part of the arch was used in a mediaeval aqueduct which, along with other tacked-on buildings, was demolished in 1930 during the fascist regime.

The current excavations are complex as the dig is taking place under the water table, at the east end of the Circus Maximus, and archaeologists have had to rebury their precious find for the time being, in line with best practice.

So far they have discovered the monument's travertine marble paving, three frontal plinths and a section of the fourth column's plinth.