It began to take shape when the municipal city, towards the end of the 12th century, began to expand beyond the vault of San Pietro, beyond the ancient Roman city which was located in the then built-up areas of the current Piazza Sordello. A large dirt land on the eastern side of the monastery of Sant’Andrea, was used as a forum for the cattle market. Once the cattle market was moved to a more peripheral location, the space in front of Via di Sant’Andrea, now Via Broletto, where stores rented to merchants had already been built, was divided in two by the Palazzo del Podestà (also called Palazzo del Broletto) and transformed into the administrative heart of the Municipality.
The square is bordered by buildings of different periods, and is closed to the north by the rear part of the Palazzo del Podestà to the east by the Palazzo della Regione, which has on its right side the Clock Tower and the Rotunda of San Lorenzo and, at the extreme right side, the so called Casa del Mercante and the adjacent Torre del Salaro.