Big Four Ice Caves, Mount Baker–Snoqualmie National Forest

Big Four Mountain is a mountain in the Cascade Range of Washington, located 21 miles east of Granite Falls. The mountain is about 6,180 ft high. At the bottom of its steep, 4,200 ft high north face, debris piles form from avalanches and are able to remain there year round because of the continuous shade provided by the mountain. At an elevation between 2,450 ft and 1,950 ft, this ice forms the lowest-elevation glacier in the lower 49 states. During the summer, snow-melt streams flow beneath the debris piles and cause caves to be formed in the ice. ()