Admiralty Island is an island in the Alexander Archipelago in Southeast Alaska, at (57°44′N134°20′W). It is 145 km (90 mi) long and 56 km (35 mi) wide with an area of 4,264.1 km² (1,646.4 sq mi), making it the seventh largest island in the United States and the 132nd largest island in the world. It is one of the ABC islands of Alaska. The island is nearly cut in two by the Seymour Canal; to its east is the long, narrow Glass Peninsula. Most of Admiralty Island — more than 955,000 acres (3,860 km²) is occupied by the Admiralty Island National Monument - a federally protected wilderness area administered by the Tongass National Forest. The Kootznoowoo Wilderness encompasses vast stands of old growth temperate rainforest.