Aniakchak National Monument and Preserve is a U.S. National Monument and National Preserve, consisting of the region around the Aniakchak volcano on the Aleutian Range of south-western Alaska.
The area was proclaimed a national monument on December 1, 1978, and established as a national monument and preserve on December 2, 1980. The national monument encompasses 137,176 acres (55,513 ha) and the preserve 464,118 acres (187,822 ha). The area is maintained by the National Park Service. With only 57 documented recreational visits in 2010, this remote place is perhaps the least visited unit of the National Park System. Most visitors fly into the area, but the frequent fog and other adverse weather conditions make landing difficult.
The Aniakchak region is part of the Pacific Ring of Fire, and the national monument consists of the caldera around Mount Aniakchak, with notable examples of several volcanic features – such as lava flows and cinder cones. Surprise Lake, located within the caldera, is the source of the Aniakchak River, a National Wild and Scenic River.