Sister cities of Unalaska, Alaska

Unalaska (Aleut: Iluulux̂) is a city in the Aleutians West Census Area of the Unorganized Borough of the U.S. state of Alaska. Unalaska is located on Unalaska Island and neighboring Amaknak Island in the Aleutian Islands off mainland Alaska.

The population was 4,376 at the 2010 census, which is 79% of the entire Aleutians West Census Area. Almost all of the community's port facilities are on Amaknak Island, better known as Dutch Harbor or just "Dutch". It is the largest fisheries port in the U.S. by volume caught. It includes Dutch Harbor Naval Operating Base and Fort Mears, U.S. Army, a U.S. National Historic Landmark.

Dutch Harbor lies within the city limits of Unalaska and is connected to Unalaska by a bridge. Amaknak Island is home to almost 59 percent of the city's population, although it has less than 3 percent of its land area.

The Aleut or Unangan have lived on Unalaska Island for thousands of years. The Russian fur trade reached Unalaska when Stepan Glotov and his crew arrived on August 1, 1759. The Unangan people, who were the first to inhabit the island of Unalaska, named it "Ounalashka" meaning ‘Near the Peninsula’. The regional native corporation has adopted this moniker, and is known as the Ounalashka Corporation.