The town hall on the north side of the cathedral piazza, completed in 1463 — the smallest and least flamboyant of the four buildings on the square. Rossellino kept it deliberately modest so as not to compete with the cathedral or the papal palace.
The ground-floor loggia is open to the street; the council chamber upstairs is occasionally accessible during exhibitions. The plain brick tower behind the building was originally a defensive structure that Pius II decided to keep when he rebuilt the town.