Piazza dell'Anfiteatro (Amphitheater Square) was built on the ruins of the ancient Roman amphitheater dating to the 2nd century AD and it was a venue for performances up to the 6th century. The closed elliptical shape is that of the ancient amphitheater.
The square was built in the Middle Ages and it was called "parlascio", a distortion of the Latin word "paralisium" (amphitheater), which, influenced by the word "parlare" (to speak), was said to indicate the place where the meetings of citizens were held.
The amphitheater was stripped of its material over the centuries to build other constructions. Later on, thanks to Carlo Lodovico in 1830, Nottolini, an architect, was commissioned with its renovation and the result is the square as we see it today. The houses follow the theater's elliptical layout and fragments can still be seen in the external parts where we see the 55 arches resting on pillars with bichrome bands of bricks alternated with stone. The one to the east is the only original Roman arch, while the others are remakes by Nottolini.