Mount Katmai

Mount Katmai is a stratovolcano on the Alaska Peninsula with a broad caldera that now holds a deep lake. The crater walls rise steeply and show layers of ash, lava, and volcanic rock, while the lake rests quietly in the center.

The major eruption of June 1912 shaped the caldera and blanketed the surrounding area with deep ash. In the years that followed, the crater filled with rainwater and snowmelt to form the lake seen today.

The name Katmai comes from the Alutiiq language and has been used for centuries. Local guides often point out how the caldera walls change color at different times of day, shifting from gray to rust red depending on the light.

Access is by floatplane or boat, as no roads reach this part of the national park. Visitors should be prepared for rapidly changing weather and bring warm, waterproof clothing for all seasons.

The crater lake hides an island of lava rock that only becomes visible when water levels drop. Geologists discovered it years after the eruption, when they began mapping the lake floor.

Location: Kodiak Island Borough

Elevation above the sea: 2,047 m

GPS coordinates: 58.27861,-154.95692

Latest update: December 5, 2025 22:28