The Staffelsee is a lake in the Garmisch-Partenkirchen district of Bavaria, Germany. The settlements of Murnau, Seehausen and Uffing lie on its shores. Within its 7 km2 (2.7 sq mi) area lie seven islands, the largest and only inhabited of which is Wörth. Wörth was the site of Staffelsee Abbey, a Carolingian monastery founded in the 8th century and dissolved in the 11th century. The main inflow and outflow of the lake is the River Ach, which enters from the west and departs to the north.