Mount Katmai is a volcano with glacier-covered walls and a large crater, located near the head of the Alaska Peninsula, in Katmai National Park. It was once much higher, but a violent eruption in 1912 collapsed the mountain. Its crater today is eight miles in circumference and 3,700 feet deep, and holds a lake with a small island. It rises near the shore of the Shelikof Straight, across which Kodiak Island can be seen. Aniakchak and the Aleutian Islands are further south on the same peninsula.