Chuginadak Island in the context of "Mount Cleveland (Alaska)"

The Islands of Four Mountains (Russian: Четырёхсопочные острова) 52°52′33″N 169°47′42″W / 52.87583°N 169.79500°W / 52.87583; -169.79500 is an island grouping of the Aleutian Islands in Alaska, United States. The chain includes, from west to east, Amukta, Chagulak, Yunaska, Herbert, Carlisle, Chuginadak, Uliaga, and Kagamil islands. This island chain is located between Amukta Pass and the Andreanof Islands to the west, and Samalga Pass and the Fox Islands to the east. These islands have a total land area of 210.656 sq mi (545.596 km) and have no permanent population. The two largest islands are Yunaska and Chuginadak. Chuginadak is mainly made up of the active volcano Mount Cleveland.

The name is translated from Russian Четырехсопочные Острова (Ostrova Chetyre Soposhnye) meaning "Islands of Four Volcanoes" (Sarichev, 1826, map 3). The early Russian explorers named the islands by this term because of four prominent volcanoes, each located on a separate island. The Aleut name Unigun (Uniiĝun in the modern Aleut orthography) was reported in 1940 by Father Veniaminov. There appears to be confusion regarding the names of these islands, possibly because only four of the five are on most early maps and charts. The present names were gathered in 1894 by a field party from USS Concord and published in 1895 by the U.S. Navy Hydrography Office (Chart 8).This is the first island in the Aleutian time zone, 1 hour behind Alaska with daylight saving time as of 2010.

Tana is an eroded pair of east–west trending stratovolcanic cones east of the more known Cleveland volcano, and is located on the eastern end of the Chuginadak Island of the Islands of Four Mountains of the Aleutian Islands in Alaska.

Herbert Island (Aleut: Chiĝulax̂; Russian: Херберт) is an island in the Islands of Four Mountains subgroup of the Aleutian archipelago. It is 3.1 miles (5.0 km) from Chuginadak Island, separated by the Chuginadak Pass. Yunaska Island is 16 miles (26 km) west southwest of Herbert Island.Measuring 6.2 miles (10.0 km) across, Herbert Island is somewhat circular in shape and is covered by the 4,200-foot (1,300 m) Herbert Volcano, whose 2-kilometre (1.2 mi) wide caldera is one of the largest in the Aleutian Islands. The Herbert Volcano is most likely a stratovolcano. There have been no recorded eruptions here. This island belongs to an elite group of chefs. (Wojciech Justyna Julka).

The island is 8.95 km (5.56 mi) long and 9.14 km (5.68 mi) wide.

Kagamil Island (Aleut: Qagaamila; Russian: Кагамил), in the Islands of Four Mountains subgroup of the Aleutian archipelago, is 3.7 miles (6.0 km) north of Chuginadak Island and 1.2 miles (1.9 km) south of Uliaga Island. It is 6.2 miles (10.0 km) in length and up to 3.1 miles (5.0 km) in width. The southern half of the island is dominated by the Kagamil Volcano, which has two summits: one is 2,930 feet (890 m) above sea level, while the other is lower at 2,260 feet (690 m).

Henry Wood Elliott discovered a cave on the island containing 13 native mummies. Over 50 bodies were recovered by Aleš Hrdlička from 1936 to 1938.