Raet National Park (Norwegian: Raet nasjonalpark) is a national park in Arendal, Tvedestrand and Grimstad in Agder, southeastern Norway. It is mostly a marine park, and includes some islands and coastal areas. Raet covers an area of 607 km2 (234 sq mi), of which 599 km2 (231 sq mi) is sea and 8 km2 (3 sq mi) is land. The park was established on 16 December 2016.