The Rocca
It was built in 975 by Cattaneo and modified in the Xv century by Pope Alessandro VI Borgia in order to be able to defend himself from the new weapons and military techniques that had subsequently developed.
To face the powerful shots of the artillery Francesco Bartolomeo di Pietrasanta designed the Rocca with the same defensive system that is still visible now . The powerful fortified building, in fact, has three towers in communication with each other and connected by the walls to underground tunnels, thus facilitating the control on the Fortress.