The vast Romanesque edifice has two chancels. The church contains a group of funerary monuments of archbishops. See the baptismal font (1328), made of pewter and decorated with delicate figures. In the western crypt is a modern gold reliquary of the saints of the diocese of Mainz. The cloister was restored in 1783. It houses the bas-relief of a Mastersinger laid to rest by the burgesses of the city in 1323.