Indre Wijdefjorden National Park is located in a steep fjord landscape in northern Spitsbergen in Svalbard, Norway. It covers the inner part of Wijdefjorden—the longest fjord on Svalbard. The national park was established on 9 September 2005 and covers 1,127 km2 (435 sq mi), of which 745 km2 (288 sq mi) is on land and 382 km2 (147 sq mi) is sea. The marine environment changes vastly from the mouth of the fjord, through a still, cold, water basin, becoming deeper before reaching the glacier Mittag-Lefflerbreen at the inner-most sections of the fjord.