One of Brittany's finest cathedrals, dating principally from the 14C and 15C. Three towers stand on the transept. Be sure to see the "bell portico" (1438), surmounted by a Flamboyant window and the Romanesque Hastings Tower (12C). The interior of the church is exceptional with its 46 Renaissance stalls and 15C funeral recesses sculpted with knights, a magnificent stained-glass window, and a remarkable treasury and cloister.