and eastern halves of Chuginadak were separate islands, and that the isthmus joining them was created by volcanic activity sometime in prehistory. The "Islands of Four Mountains" name, the geographic group name for Cleveland and its neighbors, was given to the islands by Russian cartographers in the 19th century. Its current name, Mount Cleveland, was given to it by a U.S. Coast and Geodetic Survey expedition in 1894, when it was originally observed by the USS Concord. Like the other volcanoes in the Four Islands group, which were named after prominent American politicians at the time, Mount Cleveland was named after then-president Grover Cleveland. Geography and structure Mount Cleveland is an almost symmetrical andesite stratovolcano in the Islands of Four Mountains, a volcanic group in the Aleutian Arc. Like all stratovolcanoes, Mount Cleveland grew as explosive eruptions, effusive eruptions, and lahars built it layer by layer into a convex shape. It lies southeast of Mount Carlisle and northeast of Herbert Island. Mount Cleveland forms the western half of Chuginadak Island, a broad and uneven bell-shaped landmass, and is the highest of the four volcanic islands. The island is completely uninhabited; the nearest settlement is Nikolski on Umnak Island, about eastward. Mount Cleveland is wide at its base and roughly in volume. The volcano's slope increases markedly with height, from 19° at its lower flanks to 35° near its summit. Like many other Aleutian volcanoes, Cleveland's flanks are especially rough up to , covered by multiple overlapping lava flows and debris fans that form an apron around the mountain. Lava flows are always built on top of debris flows as a result of the snow melt caused by the emission of heat just before an eruption. The flows are generally short, under , and thin, less than thick, and are somewhat vegetated. Although Mount Cleveland is the tallest mountain in the group, it is rarely completely snowed in because of its constant activity disrupts snowfall. A lack of extant erosion shows that Mount Cleveland is likely a Holocene volcano, forming within the last 10,000 years. All known events have occurred at Mount Cleveland's summit vent, but there are at least five small andesite to dacite volcanic domes on the lower flanks. At times Cleveland has had a summit lava dome. The volcano has no caldera. The eastern half of Chuginadak, to which Mount Cleveland is connected by a narrow isthmus, consists