What is the largest island in Alaska's Aleutian Islands?

The largest island in Alaska’s Aleutian Islands is Unimak Island.

Unimak is the easternmost major island in the Aleutian chain and covers about 1,571 square miles, or 4,070 square kilometres. It is considerably larger than Unalaska, Adak, and Attu, the other prominent islands often considered in this comparison. Despite its size, Unimak has a very small population.

The island is intensely volcanic. Mount Shishaldin, a near-perfect stratovolcano, rises to 9,373 feet and is among the world’s most active volcanoes. Other volcanic features include Mount Westdahl and the Fisher Caldera. Unimak’s landscape also supports brown bears, caribou, and other wildlife linked to the nearby Alaska Peninsula.

Unimak has a dramatic maritime history. Scotch Cap Lighthouse, built in 1903, was destroyed by the tsunami generated by the 1946 Aleutian earthquake, killing five Coast Guard personnel. Large parts of the island are now protected as wilderness within the Alaska Maritime National Wildlife Refuge.

A common mistake is choosing Unalaska because it is better known and more populated; Unimak is the larger island.