United States of America
Big Four Mountain is a mountain in the Cascade Range of Washington, located 21 miles (34 km) east of Granite Falls. The mountain is about 6,180 ft (1,880 m) high. At the bottom of its steep, 4,200 ft (1,300 m) high north face, debris piles form from avalanches, and these may remain there year-round
because of the permanent shade provided by the mountain. At elevations between 2,450 ft (750 m) and 1,950 ft (590 m), this ice forms the lowest-elevation glacier in the lower 49 states. During the summer, snow-melt streams flow beneath the debris piles and form caves in the ice.
Listen to the audio guide for Big Four Ice Caves Free on WIP — starts by itself when you arrive, even with the screen off