The cathedral’s round bell tower was inspired by the ancient towers of Ravenna, and is just as tilted. This formed part of the original 11th Century building although there was remodelling in the 15th and 16th centuries. The Baroque façade was added between 1632 and 1645, though it remained unfinished. Two striking bas-reliefs decorate the north portal. The interior has a single nave and contains a wooden choir and a 1529 ‘Resurrection’ by Rosso Fiorentino, in the chapel on the right-hand side. Perhaps the best painting in the Duomo is the mystical and remarkable altarpiece.