About the location (from Wiki):
Mondsee is an Austrian town in the Vöcklabruck district in Upper Austria located on the shore of the lake Mondsee. The length from north to south is 9.5 km, and width from east to west is 7.7 km. The cloister church was used for the site of the wedding in The Sound of Music. It is home to one or more prehistoric pile-dwelling (or stilt house) settlements that are part of the Prehistoric Pile dwellings around the Alps UNESCO World Heritage Site.

Movies shot at this location:
Oodha Oodha Oodha Poo song from Minsara Kanna