Heart of the city and fulcrum of its development in the Middle Ages, the square, whose structure dates back to the XII – XIII centuries, constitutes one of the most evocative and outstanding architectural bodies among the Umbrian cities, concentrating in itself valuable religious and civil monuments.
The ancient octagonal cistern, almost in the center of the square, was replaced in 1896 by the current fountain; characteristic is the Roman column, called San Rocco, planted at the beginning of the square, which was first named after Umberto I and today is dedicated to the world-famous entomologist Filippo Silvestri.