The island municipality encompasses parts of the mainland as well as three large islands: Kvaløya, Sørøya, and Seiland. Other small islands such as Lille Kamøya and Kamøya are also located here. Seiland National Park is partially located in the municipality. Seilandsjøkelen is a large glacier in the park. The Nordefjorden is a fjord that is part of the park. The mountains Komagaksla and Seilandstuva are some of the largest mountains in the municipality.