Mandalselva

Mandalselva, Mandalsåni, or Marna (English: Mandal River, ) is a river in Agder county in Norway. The river has its origins in the mountains between Ose in Setesdal and the Upper Sirdal valley. The river flows south to its mouth at the North Sea at the town of Mandal. The river is long and flows through the municipalities Åseral, Lyngdal, and Lindesnes. The largest tributaries are Monn, Logna, Skjerka, Kosåna, Logåna, and Røyselandsbekken. Skjerka, Monn and Logna all flow into the lake Øre in Åseral which is considered the beginning of the main Mandalselva river. The river passes through the villages of Kylland, Bjelland, Laudal, Heddeland, Øyslebø, and Krossen.

== Hydropower development == Hydropower development of the river on a larger scale started in 1930. At present there are six power plants along the river and its upper tributaries: Logna, Smeland, Skjerka, Håverstad, Bjelland, and Laudal.