Many eras of architectural history are clearly delineated and preserved here. The cathedral has a double nave—Romanesque and Gothic side by side—and a Merovingian (5th-century) baptistery, its colonnade mostly recovered from Roman temples built to honor pagan deities. The deep bath on the floor is a remnant of total-immersion baptism. Shutters hide the ornate 16th-century carvings on the portals, opened by a guide on request. The guide can also lead you into the tranquil Romanesque cloister next door, with carved pillars and slender columns.
The extraordinary 15th-century Triptyque du Buisson Ardent (Mary and the Burning Bush) was painted by Nicolas Froment in the heat of inspiration following his travels in Italy and Flanders and depicts the generous art patrons King René and Queen Jeanne kneeling on either side of the Virgin, who is poised above a burning bush. To avoid light damage, it's rarely opened for viewing; check with the tourist office beforehand.