The ring of buildings surrounding piazza follows the elliptical shape of the former second-century Roman amphitheater of Lucca on which the current day square is built.
A cross is carved into the central tile of the square with the arms pointing to its four gateways. The base of the former amphitheater is now some three meters below the centre.
The famous architect Notolini (who built the three-kilometre aqueduct) renovated the square by demolishing houses in the middle and building houses around the outside of it, using some. of the remaining Roman ruins.