Returning towards Piazza Cavour and crossing the large entrance hall of the Police Headquarters, you arrive at the Sant'Ilario courtyard, which overlooks the entrance to the Cathedral dedicated to Saints Ilario and Tatian.

The 14th-century building was repeatedly and severely damaged during the bombings. The collapse of the ceiling of the main nave destroyed the enormous fresco of "Paradise," painted in 1702 by Giulio Quaglio. The perimeter walls of the presbytery withstood the attacks, but the vault of the Gothic apse was breached and collapsed onto the high altar, erected in 1707 by Giovanni and Leonardo Pacassi. Paroli's fresco, behind the altar, was also entirely destroyed.