St Peter's Abbey (Stift St Peter) was founded around 696 CE by St Rupert, the patron saint of Salzburg, and may be the oldest continuously occupied monastery in the German-speaking world. The Romanesque church was converted to baroque in the 18th century, and both the monastic cloisters and the famous library (containing over 100,000 volumes, some of them 9th-century manuscripts) are still in daily use by the Benedictine community.
The real attraction for most visitors is the adjacent Petersfriedhof — St Peter's Cemetery — one of the oldest in Europe, with elaborate wrought-iron grave markers, family crypts going back to the 17th century, and the graves of Mozart's sister Nannerl, the composer Michael Haydn, and Santino Solari (architect of Salzburg Cathedral). Above the cemetery, cut into the cliff face of the Mönchsberg, are the catacombs — small hermits' chapels reached by a narrow stone stairway. The Sound of Music buffs may recognise the cemetery as the set for the scene in which the Von Trapp family hides from the Nazis.