Viterbo's Romanesque cathedral was built over the ruins of the ancient Roman Temple of Hercules. During World War II the roof and the vault of the central nave were destroyed by a bomb. Subsequently, the church was rebuilt to its original medieval design. Three popes are buried here, including Pope Alexander IV (1254–61), whose body was hidden so well by the canons, out of fear that it would be desecrated, that it has never been found. The small adjoining Museo del Colle del Duomo has a collection of 18th-century reliquaries, Etruscan sarcophagi, and a painting of the Crucifixion that has been attributed to Michelangelo.