The
Bagley Icefield (also called
Bagley Ice Valley) in southeastern
Alaska is the largest nonpolar
icefield in
North America. It was named after
James W. Bagley, a
USGS topographic engineer who developed the Bagley T-3 camera and mapped Alaska prior to
World War I. 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
Saint Elias Mountains and part of the
Chugach Mountains. It nourishes dozens of
valley glaciers that drain down both sides of the range, including the
Tana,
Miles, and
Guyot glaciers. The area of the combined Bagley Icefield and
Bering Glacier System, including tributaries, is 5,200 km² (1,900 sq mi).