Bagley Icefield, Ice field in Valdez-Cordova Census Area, United States

Bagley Icefield is a connected ice field in southeastern Alaska, in the Valdez-Cordova region, that covers most of the core of the Saint Elias Mountains and part of the Chugach Mountains. It measures 200 km long, 10 km wide and up to 1 km thick, and nourishes dozens of valley glaciers, including the Tana, Miles and Guyot glaciers.

The icefield is named after James W. Bagley, a USGS topographic engineer who developed the Bagley T-3 camera and mapped Alaska before World War I. In 1897 Luigi Amedeo, Duke of the Abruzzi, made the first ascent of Mount St. Elias without realizing that the huge glacier he crossed forms the upper reaches of the Bering Glacier, named earlier from the coast. The icefield now lies within Wrangell-St. Elias National Park and Preserve.

The ice field lies within Wrangell-St. Elias National Park and Preserve, and its name honours James W. Bagley, the USGS topographic engineer who mapped Alaska before World War I and devised the Bagley T-3 camera. Nineteenth-century climbers of Mount St. Elias, including Luigi Amedeo, Duke of the Abruzzi, who made the first ascent in 1897, did not realise this ice formed the upper reaches of the Bering Glacier, named earlier from the coast.

The area is remote and can only be reached with proper equipment and in the company of experienced guides who know the hazards of the ice. Weather changes fast in this part of Alaska, so anyone planning a visit needs to prepare carefully before setting out.

The ice reaches depths of over 3,300 feet (1,000 meters) at its thickest point and feeds several glaciers that flow outward from it, including the Guyot Glacier. That weight presses down so hard that the rock beneath the ice is actually pushed lower than it would be without it.