Setesdal is a valley and a traditional district in Agder County in southern Norway. It consists of the municipalities of Bykle, Valle, Bygland, Iveland, and Evje og Hornnes. The Otra river flows through the valley of Setesdal into the sea near Kristiansand. It flows southward from the Hardangervidda plateau in Telemark. The historic Setesdal starts at Evje and extends as far as the farm Bjåen, at the edge of the traditional region of Telemark. Øvre Setesdal is in the municipality of Bykle.