It was one of the palaces owned by Federico da Montefeltro and his wife Battista Sforza and was a fortified, palatial retreat.

Faced with the new military dangers, he had the fortress rebuilt, entrusting the task to the Sienese engineer Francesco di Giorgio Martini.

The fortress sides were equipped with artillery and the access points were rendered unreachable by enemy fire thanks to military outposts.

In 1516 the Florentine troops, supported this time by Pope Leo X and guided by Antonio Ricasoli, penetrated the city and commandeered the fort.

To the visitor who walks up the Romagna plain, the City-Fortress appears as a huge shield of high smooth rock.