On a narrow cliff ridge to the east of the village of Brienz/Brinzauls are the impressive ruins of Belfort Castle. The castle was probably built shortly after 1200 as the seat of the Lords of Vaz. In the Late Middle Ages it passed to the House of Habsburg-Austria; for this reason it was attacked and destroyed in 1499. The Barons of Vaz were Graubünden’s most powerful noble family in the 13th century, owning castles in Domleschg, Schams and in the Chur Rhine Valley.  In Chur they possessed a tower directly adjoining the wall of the Bishop’s Court. Between 2002 and 2006 Belfort underwent a conservation programme. The accompanying architectural investigations yielded a wealth of information on the origins of the medieval castle. It was thus possible to identify defensive passages, an actual defensive platform, slits for observation, galleries, a latrine projecting outwards, the guardroom and the dungeon. A gap in the north façade dates, in all probability, to the attack by League troops on 4th March 1499 prior to the Battle of Calven, which was fought below Müstair on 22nd May of the same year.