Molokai, Hawaiian Moloka‘i,  volcanic island, Maui county, Hawaii, U.S. It lies east of Oahu across the Kaiwi Channel and northwest of Maui across the Pailolo Channel. Molokai occupies 261 square miles (676 square km) and is about 38 miles (61 km) long and 10 miles (16 km) wide at its widest point. Its western and eastern portions comprise two tablelands, Mauna Loa, reaching its peak in Puu Nana (1,381 feet [421 metres]), and Kamakou (4,961 feet [1,512 metres]); these are connected by a saddle (ridge) that is 400 feet (120 metres) high. A smaller volcano formed the Kalaupapa Peninsula much later on the northern coast. Its northern side is an almost continuous towering cliff, which reaches an elevation of some 3,600 feet (1,100 metres) and is intersected by many deep valleys, including Halawa, a deep, verdant gorge 1.75 miles (2.8 km) long and 0.5 miles (0.8 km) wide and well suited to agriculture.

Molokai was long inhabited by self-sufficient taro growers and fishermen. In the 18th century the kingdom of Oahu gained control over Molokai; its rule lasted until 1785, when warriors from Maui and Hawaii islands invaded and separately ruled the island. Hawaiian chief Kamehameha I invaded in 1795 and subordinated the population as part of his effort to unify the Hawaiian Islands. Christian missionaries arrived on Molokai in the 1830s. A large ranch was established by Kamehameha V, but this destroyed much of the island’s plant life and fishing ponds. By the 1860s a colony had been begun for victims of leprosy (Hansen disease), and this led to the forced resettlement of many of the island’s natives, particularly from the Kalaupapa Peninsula, in the 1860s and 1890s. The Hawaiian Homes Commission Act of 1921 encouraged homesteading and resettlement on Molokai. Lack of water slowed development, but after 1923, with the growth of the pineapple industry, small villages grew up on the plateau. The economy of the island suffered a setback in the 1970s and 1980s when the pineapple growers, facing stiff competition from abroad, closed down their operations. Agriculture on the island is now more diversified, with coffee and sweet potatoes among the leading exports. Kaunakakai, the chief village, is on the south coast and has a small harbour. Tourism is not significant on Molokai. Notable attractions include Kalaupapa National Historical Park (1980), on the site of the former leprosy colony, and Kakahaia National Wildlife Refuge, which protects a large pond and several Hawaiian birds, including the endangered stilt.