The museum presents the cathedral's treasure and the archbishops' cabinet of curiosities (17C), as well as sacred paintings from presbyteries from around the archdiocese, dating from the Middle Ages to the present day. It also gives access to the tribunes of the organ of the cathedral, from where there is a fine view over the nave. On the square outside, Kapitelplatz, there is a monumental fountain, with a Neptune group (1732) in the centre.