The Cathedral of Mary's Ascension is the focal point of Chur's Bishop's Court. This diocese dates back to late Roman times, making this the oldest still functioning bishopric north of the Alps.

During the Protestant Reformation, the Catholic church and its adherents were exiled within this court for 300 years, conducting their lives and worship entirely cut off from the rest of the city. In the 19th century more tolerant views prevailed. The cathedral itself was founded in 1151 and bears a mixture of architectural styles, primarily Romanesque. Its grey stone, called scalära, is a common building material throughout Graubünden.