Yukon-Charley Rivers National Preserve, 2,526,512 acres (1,022,879 hectares), E central Alaska. The preserve, which protects the two river basins, near the Canadian border, contains paleontological and archeological sites, as well as old cabins and relics from the gold rush of 1898. Proclaimed a national monument in 1978, it was designated a national preserve in 1980. The 88-mi (142-km) Charley Wild River, authorized in 1980, lies entirely within the preserve. See National Parks and Monuments (table).

Wrangell-Saint Elias National Park and Preserve, at the convergence of the Chugach, Wrangell, and St. Elias mts., SW Alaska. The park (8,323,618 acres/3,369,856 hectares) contains Mt. Saint Elias (18,008 ft/5,489 m) and the nation's greatest collection of glaciers and mountain peaks above 16,000 ft (4,879 m). Together with the adjoining preserve (4,852,753 acres/1,964,677 hectares), it comprises the largest unit of the National Park System. Ruins of the Kennicott copper mines are in the park, as well as an abundance of wildlife, including Dall sheep, migrating caribou, and wolves. Proclaimed a national monument in 1978, Wrangell-St. Elias was established as a national park and preserve in 1980. See National Parks and Monuments, table.

Valles Caldera National Preserve, 88,900 acres (36,000 hectares), N N.Mex.; est. 2000. Formerly part of the vast, privately owned Baca Ranch, the preserve lies at the heart of the Valle Grande (Jemez) Mountains and encompasses most of a 12-15 mi- (19-24 km-) wide circular caldera, a sunken volcano formed by the collapse of volcanic domes after two massive eruptions about 1.6 and 1.2 million years ago. The basin is some 3,000 ft (915 m) deep, measured from the surrounding rim, which encircles several lava-dome mountains. The landscape is mainly a mixture of grasslands and forested mountains, cut by numerous streams. Like other calderas, it has hot springs, gas vents, and other volcanic features. Wildlife include 17 threatened or endangered species such as the Mexican spotted owl, goshawk, Jemez Mountains salamander, and Rio Grande cutthroat trout. The preserve also is home to elk, mule deer, black bears, mountain lions, coyotes, bobcats, and other mammals, and golden and bald eagles and other birds.

Timucan Ecological and Historic Preserve: see National Parks and Monuments (table).

Tallgrass Prairie National Preserve: see National Parks and Monuments (table).

Salt River Bay National Historical Park and Ecological Preserve: see National Parks and Monuments (table).

Noatak National Preserve, 6,569,904 acres (2,660,811 hectares), N Alaska. The preserve is the largest mountain-ringed river basin in the United States that is still virtually unaffected by human activities. It is a transition zone for plants and animals between arctic and subarctic environments and includes the Grand Canyon of the Noatak River. Proclaimed a national monument in 1978, it was designated a national preserve in 1980. The 330-mi (531-km) Noatak Wild River, authorized in 1980, lies partially within the preserve and partially in the Gates of the Arctic National Park and Preserve. See National Parks and Monuments (table).

Mojave National Preserve: see Mojave Desert; National Parks and Monuments (table).

Little River Canyon National Preserve: see National Parks and Monuments (table).

Lake Clark National Park and Preserve, S Alaska. Located across Cook Inlet from Anchorage, the park (2,619,733 acres/1,060,621 hectares) and adjacent preserve (1,410,325 acres/570,982 hectares) feature the jagged peaks of the Chigmit Mts; lakes Clark, Fishtrap, and Iliamna; volcanoes; glaciers; and abundant wildlife. Also within the park and preserve are the 11-mi (18-km) Chilikadrotna Wild River, the 24-mi (39-km) Mulchatna Wild River, and the 51-mi (82-km) Tlikakila Wild River, all authorized in 1980. Lake Clark was proclaimed a national monument in 1978 and became a national park and preserve in 1980. In 1989 and 1990 the Mount Redoubt volcano erupted, dropping ash on Anchorage. See National Parks and Monuments (table).

Katmai National Park and Preserve, at the northern end of the Alaska Peninsula on Shelikof Strait, S Alaska, comprising Katmai National Park (3,674,530 acres/1,487,664 hectares) and an adjoining preserve (418,699 acres/169,514 hectares). Established in 1918 as a national monument, it was later expanded and was designated a park and preserve in 1980. Mt. Katmai and Novarupta volcanoes and the Valley of the Ten Thousand Smokes are located in this region, which is the site of one of the greatest volcanic eruptions in history, that of Novarupta in 1912. All plant and animal life in the area was destroyed by the ash and lava, although no people were reported killed. Kodiak Island, 100 mi (160 km) to the southeast, was covered with c.1 ft (.3 m) of ash. As lava beneath Mt. Katmai drained W to Novarupta, its top collapsed, forming a crater 8 mi (12.8 km) in circumference and 3,700 ft (1,128 m) deep, in which a lake has formed. The Valley of the Ten Thousand Smokes (72 sq mi/186 sq km) has countless holes and cracks through which hot gases passed to the surface; all but a few have become extinct. The park also includes glacier-covered peaks, crater lakes, a coastline with dramatic fjords and waterfalls, dense marshlands, and heavy forests with a variety of wildlife, notably moose and grizzly bears. See National Parks and Monuments (table).

Great Sand Dunes National Park and Preserve: see National Parks and Monuments (table).

Glacier Bay National Park and Preserve, SE Alaska, near Juneau. The park (3,224,840 acres/1,305,603 hectares) and the preserve (58,406 acres/23,646 hectares) were established in 1925 as a national monument and in 1980 designated a national park and preserve. Glaciers descending from the towering snow-covered mountains of the Fairweather Range into the bay create one of the world's most spectacular displays of ice. Among the bay's most famous glaciers is Muir Glacier, c.2 mi (3.2 km) wide and rising c.265 ft (80 m) above the water. Wildlife includes bears, deer, mountain goats, porpoises, whales, and waterfowl. See National Parks and Monuments (table).

Gates of the Arctic National Park and Preserve, N Alaska. Located N of the Arctic Circle, the park (7,523,898 acres/3,046,113 hectares) and adjacent preserve (948,629 acres/384,060 hectares) make up the second largest unit of the National Park System. Gates of the Arctic is a tundra wilderness of broad valleys and the razorlike peaks of the Brooks Range, and is known for its abundance of arctic caribou, grizzly bears, moose, and wolves. It was proclaimed a national monument in 1978 and designated a national park and preserve in 1980. Within the park and preserve are the 83-mi (134-km) Alatna Wild River, the 52-mi (84-km) John Wild River, the 110-mi (177-km) Kobuk Wild River, part of the 330-mi (531-km) Noatak Wild River, the 102-mi (164-km) North Fork of the Koyukuk Wild River, and the 44-mi (71-km) Tinayguk Wild River, all of which were authorized in 1980. See National Parks and Monuments (table).

Denali National Park and Preserve, in the Alaska Range, S central Alaska; comprising Denali National Park (4,740,912 acres/1,919,398 hectares), est. as Mt. McKinley National Park 1917, and Denali National Preserve (1,399,078 acres/566,428 hectares), est. as a national monument 1978. The two were combined under the above name in 1980. Located in a region of spectacular mountain scenery, the park contains Mt. McKinley (Denali), the highest point in North America (20,320 ft/6,194 m). Many peaks exceed 10,000 ft (3,048 m). There are glaciers, tundra, and abundant wildlife (moose, mountain sheep, grizzly bears, and wolves). See National Parks and Monuments (table).

Big Thicket National Preserve: see National Parks and Monuments (table).

Big Cypress National Preserve: see National Parks and Monuments (table).

Aniakchak National Monument and Preserve, on the Alaska Peninsula, SW Alaska. Located in the Aleutian Range, the monument (137,176 acres/55,556 hectares) and surrounding preserve (465,603 acres/188,569 hectares) feature the Aniakchak volcano (4,420 ft/1,347 m high), which last erupted in 1931. Aniakchak was proclaimed a U.S. national monument in 1978 and established as a national monument and preserve in 1980. The Aniakchak's caldera is c.6 mi (9.7 km) in diameter and contains Surprise Lake, the source of the 63-mi (101-km) Aniakchak Wild River. The surrounding preserve has many varieties of wildlife. See National Parks and Monuments, table.

National park, southeastern Alaska, U.S. Proclaimed a national monument in 1978, the area underwent boundary and name changes in 1980. The largest park in the U.S. national park system, it has an area of 12,318,000 ac (4,987,000 ha). At the convergence of the Chugach, Wrangell, and Saint Elias mountain ranges, it includes the largest assemblage of glaciers and the greatest collection of peaks above 16,000 ft (4,880 m) on the continent.

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National park, southern Alaska, U.S. Located on the western shore of Cook Inlet, it was proclaimed a national monument in 1978 and a national park in 1980. Its total area is 3,653,000 acres (1,478,300 hectares). Lake Clark, more than 40 mi (65 km) long, is the largest of its glacial lakes; it feeds rivers that provide the most important spawning ground for red salmon in North America. The park includes glaciers, waterfalls, and active volcanoes.

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National park, southwestern Alaska, U.S., at the head of the Alaska Peninsula. Occupying an area of 4,090,000 acres (1,655,000 hectares), it was proclaimed a national monument in 1918 after the eruption of Novarupta in 1912. The eruption converted the valley into a wasteland known as the Valley of Ten Thousand Smokes, and the volcanic crater later became a lake. The park abounds in wildlife, including large numbers of brown and grizzly bears.

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Natural area, south-central Colorado, U.S. It lies at the eastern edge of the San Luis Valley along the western base of the Sangre de Cristo Mountains. Established in 1932 as a national monument, the 150,000-acre (60,700-hectare) region contains some of the highest inland sand dunes in the U.S., with changing crests that rise to 700 ft (215 m). In 2000 the Great Sand Dunes National Preserve was created, and after much land acquisition the monument officially became a national park in 2004.

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Natural area, southeastern Alaska, U.S. Located on the Gulf of Alaska, it was proclaimed a national monument in 1925, established as a national park and preserve in 1980, and designated a World Heritage site in 1992. It covers 5,040 sq mi (13,053 sq km). It includes Glacier Bay, much of Mount Fairweather, and the U.S. portion of the Alsek River. Among its great tidewater glaciers is Muir Glacier, which rises 265 ft (81 m) above the water and is nearly 2 mi (3 km) wide. The park also includes a dramatic range of plant species and such wildlife as brown and black bears, mountain goats, whales, seals, and eagles.

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National preserve, northern Alaska, U.S. Its area of 11,756 sq mi (30,448 sq km) is entirely north of the Arctic Circle. Proclaimed a national monument in 1978, the area underwent boundary changes and was renamed in 1980. It includes a portion of the Central Brooks Range. The southern slopes are forested, contrasting with the barren northern reaches at the edge of Alaska's North Slope.

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Preserve, southern central Alaska, U.S. Established in 1980, it comprises the former Mount McKinley National Park (1917) and Denali National Monument (1978). Highlights of the park include Mount McKinley, the large glaciers of the Alaska Range, and abundant wildlife. The park's total area is 5,000,000 acres (2,025,000 hectares).

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Park, southern shore of the Alaska Peninsula, U.S. Situated in the volcanically active Aleutian Range, it consists primarily of a great dry caldera, which last erupted in 1931. The crater has an average diameter of 6 mi (10 km). Declared a national monument in 1978, it covers 942 sq mi (2,440 sq km).

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