More proof that the Eternal City is the gift that keeps on giving, with the discovery of a two-metre pomerial stone or cippus made from travertine, which was excavated by workmen laying sewers in the piazza where the newly-opened Mausoleum of Augustus in central Rome is situated.

The mausoleum lies between the Lungotevere and Piazza di Spagna and the limestone rock was found in June.

The boundaries of ancient Rome comprised of a strip of land called a pomerium which was considered sacred. Weapons and agricultural activities were banned on the land. Such rocks defined the ancient city’s boundaries and were placed outside the exterior walls, giving us a clue as to where ancient Rome ended.

At one time this area would have been the far boundary of an area in the city called the Campus Martius

The tradition of the pomerium was established by the first mythical king of Rome, Romulus – who famously killed his twin brother Remus.

It is thought that the stone dates from the reign of Emperor Claudius (10 BC – 54 AD) and is estimated to date from 49 AD. It is one of only 11 known to exist.

The rock will now be displayed inside the Ara Pacis Augustae, which is next to the mausoleum.

Read more about the discovery at Live Science and Smithsonianmag.com.

Featured image: Edge of the piazza where the stone was dug up by workmen. (Image A. Meredith 2019)