The Riccardo Arch is located in the square behind the church of San Silvestro and is the oldest monument from Roman origin survived untill the present day. Its structure is fairly similar to the triumphal arches that the Romans used to erect in honor of victorious generals although it is actually a monumental gate of the city walls, built around 50 BC When the walls were torn down during the first century A.D. to enable the development of the city, this beautiful gate was left intact just like a triumphal arch. The name comes from the popular belief that this arch was erected in honor of King Charlemagne (King Charles becomes Ri Cardo). Another belief says that in a tower that once stood in this square was imprisoned King Richard the Lionheart, waiting for the payment of ransom. His name would be later passed to the square and to the arch.