The Otra river flows through the valley of Setesdal into the sea near Kristiansand. Otra flows from the Hardangervidda plateau in Telemark to the north. The historic Setesdal starts at Evje and extends as far as the farm Bjåen, at the edge of Telemark county. Øvre (Upper) Setesdal is in the municipality of Bykle. The municipalities of Iveland, Evje & Hornes and Bygland comprise the Nedre (Lower) Setesdal. Valle municipality is in the middle of the Setesdal valley. Norwegian National Road 9 runs through Setesdal.