The Gudbrandsdalslågen (or simply Lågen) is a river which flows through the Gudbrandsdal valley in Innlandet county, Norway. The 204-kilometre (127 mi) long river runs through a large valley in Eastern Norway before emptying into Mjøsa, the largest lake in Norway. The river flows through the municipalities of Lesja, Dovre, Sel, Nord-Fron, Sør-Fron, Ringebu, Øyer, and Lillehammer.
