Kaho'olawe is the smallest of the eight main volcanic islands in the Hawaiian Islands. Kaho'olawe is located about seven miles (11.2 km) southwest of Maui and also southeast of Lanai, and it is 11 miles (18 km) long by 6.0 miles (9.7 km) wide, with a total land area of 44.6 square miles (115.5 km2).
The highest point on Kahoolawe is the crater of Lua Makika at the summit of Puʻu Moaulanui, which is about 1,477 feet (450 m) above sea level. Kahoolawe is relatively dry (average annual rainfall is less than 65 cm/26 in) because the island's low elevation fails to generate much orographic precipitation from the northeastern trade winds, and Kahoolawe is located in the rain shadow of eastern Maui's 10,023 feet (3,055 m) high volcano, Haleakalā. More than one quarter of Kahoolawe has been eroded down to saprolitic hardpan soil.
Kahoolawe has always been sparsely populated, due to its lack of fresh water. During World War II, Kahoolawe was used as a training ground and bombing range by the Armed Forces of the United States. After decades of protests, the U.S. Navy ended live-fire training exercises on Kahoolawe in 1990, and the whole island was transferred to the jurisdiction of the State of Hawaii in 1994. The Hawaii State Legislature established the Kahoolawe Island Reserve to restore and to oversee the island and its surrounding waters. Today Kahoolawe can be used only for native Hawaiian cultural, spiritual, and subsistence purposes.
The U.S. Census Bureau defines Kahoolawe as Block Group 9, Census Tract 303.02 of Maui County, Hawaii. Kahoolawe has no permanent residents.