Mount Sanford is a shield volcano in the Wrangell Volcanic Field, in eastern Alaska near the Copper River. It is the third highest volcano in the United States behind Mount Bona and Mount Blackburn. The south face of the volcano, at the head of the Sanford Glacier, rises 8,000 feet (2,400 m) in 1 mile (1,600 m) resulting in one of the steepest gradients in North America.
Mount Sanford is mainly composed of andesite, and is an ancient peak, being mostly Pleistocene, although some of the upper parts of the mountain may be Holocene. The mountain first began developing 900,000 years ago, when it began growing on top of three smaller shield volcanoes that had coalesced. Two notable events in the mountain's history include a large lava flow which traveled some 11 miles (18 km) to the north east of the peak, and another flow which erupted from a rift zone on the flank of the volcano some 320,000 years ago. The second flow was basaltic in nature and marks the most recent activity of the volcano. The flow was dated using radiometric methods.
Prominence: 7,637 ft (2,328 m)
Peak elevation: 16,237 ft (4,949 m)