Arjeplog Municipality is a municipality in Norrbotten County, in northern Sweden, where Arjeplog (Northern Sami: Arjepluovve) is the seat with 2,000 inhabitants. Arjeplog is Sweden's fourth largest municipality, but the fourth least populated. It is located by the shores of lake Hornavan, Sweden's deepest lake and one of its largest. The municipality is popular because of the scenery of lake Hornavan, but also of its other untouched nature. Arjeplog municipality consists of a terrain dominated by the Scandinavian mountain range and many water areas. It boasts an unparallelled 8,000 lakes and streams, with three main rivers being the Pite River, Skellefte River and Lais River. The Skellefte River attaches south from lake Hornavan, and extends south-east to Skellefteå and the Gulf of Bothnia on the east coast. Arjeplog also has 13 nature reserves, mostly mountain moorland, where endangered plants grow. Mountain Galtispuoda, with a height of 800 metres, is both a popular place of outlook, a nature reserve, and in the winter a popular place for skiing.