It was built in the Gothic-Romanesque and Renaissance style, while elements of the façade date back to the fifteenth century. From the Fifteenth Century, construction of the cathedral witnessed cutting of two arches to the south (1477 ) and the closing of a porch on the same side (1514 ). This removal resulted in the separation of the municipal building commonly referred to as "Broletto" in the West and "Praetorian" to the east. This also necessitated a change in the level of the square, which was raised, as you can see even today observing the base of the pillars on the porch.
The Broletto Como - side via Praetorian (northeast) Once lost its civic function the Broletto, starting from 1764 , it became the seat of a theater and later was used as a store.