Big Four Ice Caves

Useful Information

Location: Mount Baker-Snoqualmie National Forest, east of Granite Falls.
Open: No restrictions.
Fee: free.
Classification: SpeleologyGlacier cave
Light: bring torch
Guided tours: n/a
Photography: allowed
Accessibility: no
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


2006 bridge destroyed.
2009 bridge replaced.
31-JUL-2010 11 year old Grace Tam killed by falling ice.


Big Four Ice Cave inside. Public Domain.

Big Four Ice Caves are two glacier caves located at the foot of Big Four Mountain, WA. On the eastern flank of the mountain an ice field named Big Four Glacier contains regularly, almost every year, two glacier caves. The ice field is formed by the winter snow going down into the valley in frequent avalanches, so it is actually not a glacier. The snow accumulates at the foot of the mountain and forms ice. During summer much of the ice melts away, but some remains typically stay all summer in the shady and cool valley on the northeastern flank of the mountain. The melting water running down from the mountain crosses the ice field and forms the caves. The caves are visible only during summer and early autumn, in winter and spring they are filled with ice and snow. Actually they form newly every year, so one could say there is a new set of caves every year.

There is a trail from the nearby Mountain Loop Highway. The trail is well developed with a rather new bridge across the Stillaguamish River. But the trail ends at some distance from the caves, and there ar numerous warning signs. Actually a visit of the inside is rather dangerous and not encouraged. The problem is frequently falling ice, as the caves only exist during the melting phase of the ice. There will be melting water dripping from the ceiling and rivers running through the cave. Appropriate clothes and helmet are absolutely necessary for such a dangerous visit. Or even better: stay away far enough.

Those warnings are not just the typical American avoid-to-be-sued warnings, there is a real danger. On 31-JUL-2010 the 11 year old Grace Tam died in front of the cave. She looked at the cave from a point about five meters in front of the entrance, when a huge chunk of ice the size of a car fell down and hit her. Nurses who were hiking nearby performed CPR for more than an hour, but Grace died at the scene. The parents now suggest safety improvements like clearly marked areas telling hikers where they should and shouldn't go. This might be rather futile, because the situation changes continually due to the moving and melting ice.