Kahoolawe (; Hawaiian: ) is the smallest of the eight main volcanic islands in the Hawaiian Islands. Kahoolawe is located about seven miles (11.2 km) southwest of Maui and also southeast of Lanai, and it is long by wide, with a total land area of . The highest point on Kahoolawe is the crater of Lua Makika at the summit of Puu Moaulanui, which is about above sea level. Kahoolawe is relatively dry (average annual rainfall is less than ) 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 high volcano, Haleakala. More than one quarter of Kahoolawe has been eroded down to saprolitic hardpan soil.