ʻĪao Valley is a lush, stream-cut valley in West Maui, Hawaii, located 3.1 miles west of Wailuku. Because of its natural environment and history, it has become a tourist location. It was designated a National Natural Landmark in 1972.
Wikipedia https://en.wikipedia.org/wiki/Iao_Valley
Official website http://www.hawaiistateparks.org/parks/maui/index.cfm?park_id=36
Address 96793, United States
Coordinates 20°52'51.985" N -156°32'47.735" E