The Arch of Janus stands in Rome’s Velabrum, near the Forum Boarium and a short walk from the Mouth of Truth. Built in the fourth century, it is a square, four-sided arch with a passage on each side, an unusual form known as quadrifrons. Look for the empty statue niches and reused stone and marble in its construction. The surrounding area was once a hub of trade and movement; today, the arch makes a brief, quieter stop alongside nearby ancient sites.
A four-sided arch in the Velabrum
The Arch of Janus stands at the northeastern edge of the Forum Boarium, Rome’s ancient cattle market and a trading area. Its square plan has an arched opening on each side, so the structure has no single front or back. This design is known as quadrifrons.
Built in the fourth century, the arch is the only surviving quadrifrons arch in Rome. Its position at a place where routes met may have served a practical civic or commercial purpose. Its exact original function is not known, and its name does not establish a religious purpose.
Stone, niches and a changed silhouette
The arch was built with materials taken from earlier structures, including marble and other reused elements. Empty niches around its exterior once held statues. Worn details remain in the stone, though the structure has changed over time.
A staircase in one of the piers once led to rooms above. Later additions on top of the arch were removed in the early nineteenth century, when they were considered medieval. The result is the shortened outline visible today.
Planning a short visit
The arch is on Via del Velabro, close to the Mouth of Truth and Santa Maria in Cosmedin. It works well as a brief stop while visiting those nearby sites or the ancient temples at Piazza della Bocca della Verità.
You can see the structure clearly from the surrounding area, but access to the space immediately around it has been restricted at times. Check whether the barriers are open if walking through the arch is important to your visit. Lighting added in recent years makes the monument visible after dark.
FAQ
Where is the Arch of Janus?
It is on Via del Velabro in Rome, near the Forum Boarium, the Mouth of Truth and Santa Maria in Cosmedin.
What makes the Arch of Janus unusual?
It has four sides, each with an arched opening. It is the only surviving quadrifrons arch in Rome.
Can you walk through the Arch of Janus?
Access close to the arch may be restricted. Check whether the barriers are open before planning to pass through it.
How long should I allow for a visit?
Allow about 10 to 20 minutes to see the arch. It is easy to combine with nearby sites.
