Shishaldin Volcano, or Mount Shishaldin, is one of six active volcanoes on Unimak Island in eastern the Aleutian Islands of Alaska. It is the highest mountain peak of the Aleutian Islands, rising to a height of 9,373 ft above sea level. Shishaldin's magma supply is generated via flux melting above the Aleutian Trench, where the Pacific Plate subducts beneath the North American Plate.