Jeju Island (Korean: 제주도; Hanja: 濟州島) is an island in the Jeju Province of South Korea. The island lies in the Korea Strait, below the Korean Peninsula, south of the South Jeolla Province. The island contains the natural world heritage site, Jeju Volcanic Island and Lava Tubes.Jeju has a moderate climate; even in winter, the temperature rarely falls below 0 °C (32 °F). Jeju is a popular holiday destination and a sizable portion of the economy relies on tourism and economic activity from its civil/naval base.