Expression of Renaissance architecture in Romagna, is of Tuscan influence. Its construction, designed by Giuliano da Maiano, began in 1474, and did not end before 1515, but the facade remained unfinished. The interior of the cathedral features a Latin cross-shaped plant with three aisles separated by round arches resting on Ionic columns alternating with columns. The aisles are flanked by eight chapels per side. The deep apse ends with a shell shaped like a shell and is illuminated by five high monofore. Behind the main altar, in polychrome marble, there is the wooden chorus of 1513. The cathedral houses works of art from Renaissance period, especially sculptures.