Tovdalselva or Topdalselva (literally: the Tov valley river) is long and is one of the longest rivers in Southern Norway. The river flows from the northeast to the southwest and reaches the sea at the Tofdalsfjorden between Hamresanden and Kjevik. The upper reaches of the river include many lakes such as the Herefossfjorden and the Straumsfjorden (the largest lake on the river). It drains about in territory and the highest point is above sea level. The drainage basin includes parts or all of the following municipalities: Fyresdal, Valle, Bygland, Evje og Hornnes, Åmli, Froland, Grimstad, Birkenes, Iveland, Lillesand, and Kristiansand.

Tovdalselva or Topdalselva (literally: the Tov valley river) is long and is one of the longest rivers in Southern Norway. The river flows from the northeast to the southwest and reaches the sea at the Tofdalsfjorden between Hamresanden and Kjevik. The upper reaches of the river include many lakes such as the Herefossfjorden and the Straumsfjorden (the largest lake on the river). It drains about in territory and the highest point is above sea level. The drainage basin includes parts or all of the following municipalities: Fyresdal, Valle, Bygland, Evje og Hornnes, Åmli, Froland, Grimstad, Birkenes, Iveland, Lillesand, and Kristiansand.