Unalaska is an island in the Fox Islands group of the Aleutian Islands in the U.S. state of Alaska. The island has a land area of 1,051 square miles. The city of Unalaska, Alaska, covers part of the island and all of neighboring Amaknak Island where the Port of Dutch Harbor is located. According to the Census of 2000, the population of the island excluding Amaknak was 1,759.
Unalaska is the second-largest island in the Fox Islands group and the Aleutian Islands. The coastline of Unalaska is quite different in appearance than other major Aleutian Islands, with many inlets and peninsulas. The irregular coastline is broken by three long deep bays, Beaver Inlet, Unalaska Bay, and Makushin Bay, as well as by numerous smaller bays and coves. Unalaska's terrain is rugged and covered with mountains, and during the greater part of the year the more elevated regions are covered with snow.