IAO

valley, Maui county, northwestern Maui Island, Hawaii, U.S., on the eastern slope of Puu Kukui Mountain. Formed by erosion of the caldera whose volcano created the island's western peninsula, the valley comprises a deep, narrow gorge 5 miles (8 km) long and flanked by heavily forested walls almost a mile in height. Iao Needle, a volcanic monolith 2,250 feet (686 m) high, soars nearly straight up from the valley floor. A bronze tablet at its base commemorates the bloody 1790 battle of Kepaniwai (meaning dammed stream, referring to the blockage of the torrent by the bodies of Maui warriors), which added Maui to the kingdom of Kamehameha the Great. Kepaniwai Park and Heritage Gardens, near the valley entrance and Wailuku, has landscaped gardens representing Hawaii's various cultures. Iao Stream is dammed there to provide wading and swimming pools.