A UNESCO World Heritage Site and one of the great Gothic cathedrals of France. The west facade is unique — five portals instead of the usual three — and the 13th-century stained glass windows are among the finest in the country, rivaling those of Chartres. The unusual interior, with double aisles and no transept, gives the cathedral a sense of vertiginous height and light that few other medieval buildings match.
Climb the north tower (around 400 steps) for a view across the marshes and the Berry plain. The astronomical clock in the south aisle, made in 1424, still works. Open daily, roughly 8am to 6pm; check times for the tower and the crypt separately.