is municipality in Agder county, Norway. It is located in the traditional district of Sørlandet. The administrative center is the town of Tvedestrand. There are many villages in the municipality including Dypvåg, Fiane, Gjeving, Gødderstad, Grønland, Kilen, Klåholmen, Krokvåg, Laget, Lyngør, Nesgrenda, Østerå, Sagesund, Sandvika, and Songe.

Southern Norway is the geographical region (landsdel) along the Skagerrak coast of southern Norway. The region is an informal description since it does not have any governmental function. It roughly corresponds to the old petty kingdom of Agder being coextensive with the county, as well as the two former counties of Vest-Agder and Aust-Agder. From New Year 2020, the two counties have been merged into one county, Agder. The total combined area of Vest-Agder and Aust-Agder counties is 16,493 square kilometres (6,368 sq mi). The name is relatively new, having first been used in Norway around 1900.