The Mondsee is a lake in the Upper Austrian part of the Salzkammergut and neighbour to the larger Attersee. Its southwestern shore marks the border between the states of Upper Austria and Salzburg, and also between the Northern Limestone Alps in the South and the Sandstone zone of the Northern Alps. The Drachenwand (Dragonwall) at the southern shore of the lake is an impressive sight.

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. There is features a church used for the site of the wedding in The Sound of Music.