Aniakchak National Monument and Preserve

Rafting a wild river

This monument is home to a deep caldera formed during a massive volcanic eruption 3,500 years ago

Aniakchak National Monument and Preserve is a stark reminder of Alaska's location in the volcanic "Ring of Fire." Located on the road less Alaska Peninsula, 150 miles southwest of King Salmon, this 586,000-acre monument is home to one of the world's largest calderas.

History

Aniakchak Caldera is 6 miles wide, 2,500 feet deep and the result of a 7,000-foot volcano collapsing during a massive eruption that occurred 3,500 years ago. The Aniakchak National Monument and Preserve was established to recognize the unique geological significance of the Aniakchak caldera. Scientists soon discovered, though, that the area has a rich cultural history.

The oldest known archaeological sites date to around 2,000 years ago, and the archaeological record shows that prehistoric communities hunted, fished, trapped, picked berries and gathered shellfish up through the historic era. With industrialization, Aniakchak residents took up commercial fishing and built cannery operations that continue today in the lower Alaska Peninsula area. The Alutiiq people that descended from the early inhabitants of Aniakchak maintain subsistence and cultural traditions today.

Ecosystem

Inside the caldera are cinder cones, lave plugs, hot springs, Sunrise Lake and Vent Mountain, a 2,200-foot cone. If the weather is clear both the Pacific Ocean and the Bearing Sea can be seen from its rim.

The weather, however, is rarely clear. The coastal area of the park is often shrouded in fog and rain while in and around the caldera the weather is often long periods of cold, rainy and windy conditions. Due to its notoriously bad weather, making it difficult for bush planes to land in its remote location, Aniakchak is one of the least visited units of the National Park System, attracting less than 200 visitors a year.

Wildlife

The monument is home to the Aniakchak River, a designated wild river. Brown bears, moose and caribou. Aniakchak Bay provides habitat for seals, sea otters and sea birds. The parkland’s boundaries also contain other important resources. West of the caldera lies the waterfowl and migratory bird habitat of Bristol Bay's coastal plain. To the east, rugged bays and inlets of the Pacific coast and offshore islands provide habitat for sea mammals and sea birds.

Activities

The most common activities pursued in the park are hiking the caldera floor, sport fishing and floating the Aniakchak River. Designated a National Wild River, the Aniakchak begins gently at Surprise Lake and then speeds up as it flows through The Gates, a narrow, 1,500-foot-high canyon in the caldera wall. The river drops more than 1,000 feet in elevation within the first 15 miles leaving the caldera, swirling past boulders the size of small cars and makes it challenging to even veteran rafters. It flows through a treeless terrain of rolling grasslands, and after 32 miles empties into the Pacific Ocean at Aniakchak Bay.

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