The square is overlooked by the original façade of the cathedral. Until 1899 known as the “Piazza del Papa” because of the bronze statue of Julius III by Vincenzo Danti, it was named after the artist only after the statue was moved to allow for the passage of electric tramcars. 
In the Middle Ages the square was the site of a farmers market, as shown by the little bas-reliefs of hands holding ears of corn, sculpted on the corners of Palazzo del Turreno in the direction of Via Bartolo and Via del Sole; it is still today the site of a potters market.