The Cathedral of Saint Mary of the Assumption (German: Kathedrale St. Mariä Himmelfahrt) is the Roman Catholic cathedral of the diocese of Chur in Switzerland. The episcopal palace of the bishop of Chur is beside the church. The cathedral claims the relics of St Lucius of Britain, said to have been martyred nearby in the late 2nd century. During the Swiss Reformation, the Catholic population of the city were confined to a ghetto enclosed around the bishop's court beside the cathedral.
The first building on the site probably dates from the first half of the 5th century. The Romanesque crypt was probably built under Bishop Tello (758-73). It contains remarkable paintings by Albrecht Dürer and Hans Holbein. The current building was built between 1154 and 1270. In 1272 it was dedicated to Saint Mary of the Assumption. The round arch window along the center axis is the largest medieval window in Graubünden. The late-Gothic high altar was completed in 1492 by Jakob Russ.
The cathedral was renovated from 2001 to 2007.
Coordinates: 46°50′52″N 9°32′07″E / 46.84778°N 9.53528°E