Altmünster (Central Bavarian: Oidmünsta), also known as Altmünster am Traunsee, is a market town located about 3 kilometres south of Gmunden in the Austrian state of Upper Austria, on the west shore of the Traunsee. Its economic base consists primarily of tourism, light industry, and as a bedroom community for people working in larger communities such as Gmunden and Vöcklabruck.