One of the city’s most unique churches. The complex consists of two churches, one above the other, where the 10th-century Romanesque style blends impressively with the 11th-century Gothic style.

The lower church was built during the 11th–12th centuries on the remains of an earlier church and is dedicated to Saints Fermo and Rustico, who were executed at this site. In the 14th century, the upper church was established by the Franciscan order, introducing Gothic elements, and over the years wall paintings, spires, and other symbols were added.

The church façade clearly shows this combination: a lower section with a Romanesque entrance and an upper section of alternating tuff and terracotta stones, featuring four Gothic-style windows and prominent spires that draw the eye upward. The entrance door displays 24 panels depicting the story of the two saints.

Inside, the church has a magnificent wooden ceiling with five longitudinal sections and side chapels. Among the ancient paintings and sculptures on the right, there is a passage leading to the lower church and the Romanesque cloister.