The Bagley Icefield in southeastern Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 is the largest nonpolar icefield in North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. It was named after James W. Bagley, a USGS

United States Geological Survey

The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology,...

 topographic

Topography

Topography is the study of Earth's surface shape and features or those ofplanets, moons, and asteroids...

 engineer who developed the Bagley T-3 camera and mapped Alaska prior to World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

. At 200 km (127 mi) long, 10 km (6 mi) wide, and up to 1 km (3,000 ft) thick, it covers most of the core of the Chugach Mountains

Chugach Mountains

The Chugach Mountains of southern Alaska are the northernmost of the several mountain ranges that make up the Pacific Coast Ranges of the western edge of North America. The range is about 500 km long, running generally east-west. Its highest point is Mount Marcus Baker, at , but most of its...

. It nourishes dozens of valley glaciers that drain down both sides of the range, including the Tana

Tana Glacier

Tana Glacier is a 17-mile-long glacier in the U.S. state of Alaska. It begins at Bagley Icefield and flows northwest to its 1950 terminus near the head of the Tana River. Its name, of Alaska Native origin, was first recorded by prospectors in 1900....

, Miles

Miles Glacier

Miles Glacier is a -long glacier in the U.S. state of Alaska. It flows west to its terminus at Miles Lake , north of Goat Mountain and north of Katalla. It was named in 1885 after U.S. Army Maj. Gen. Nelson A. Miles by a Lt. Allen during his Alaska expedition.- References :...

, and Guyot

Guyot Glacier

Guyot Glacier is a long and wide glacier located in the east end of the Robinson Mountains in the U.S. state of Alaska. It begins north of Yaga Peak and heads east-southeast to Icy Bay, south of the Guyot Hills and northwest of Yakutat. It borders Yahtse Glacier on the northeast. The glacier...

 glaciers. The area of the combined Bagley Icefield and Bering Glacier

Bering Glacier

Bering Glacier is a glacier in the U.S. state of Alaska. It currently terminates in Vitus Lake south of Alaska’s Wrangell-St. Elias National Park, about from the Gulf of Alaska. Combined with the Bagley Icefield, where the snow that feeds the glacier accumulates, the Bering is the largest glacier...

 System, including tributaries, is 5,200 km² (1,900 sq mi).

Nineteenth-century explorers attempting to climb Mt. St. Elias

Mount Saint Elias

Mount Saint Elias, also designated Boundary Peak 186, is the second highest mountain in both Canada and the United States, being situated on the Yukon and Alaska border. It lies about southwest of Mount Logan, the highest mountain in Canada. The Canadian side is part of Kluane National Park,...

, including Luigi Amedeo, Duke of the Abruzzi, who successfully made the first ascent in 1897, did not recognize that the huge glacier now named Bagley Icefield actually forms the upper reaches of the distant and similarly vast Bering Glacier, which had been named earlier, after observation from the coast.

The glacier is protected within the boundaries of the Wrangell-St. Elias National Park and Preserve

Wrangell-St. Elias National Park and Preserve

Wrangell–St. Elias National Park and Preserve is a United States National Park in southeastern Alaska. It was established in 1980 by the Alaska National Interest Lands Conservation Act. The park area is included in an International Biosphere Reserve and is part of a UNESCO World Heritage Site...

.