Jeju Island is the largest island off the coast of the Korean Peninsula, and the main island of Jeju Province of South Korea. The island lies in the Korea Strait, south of South Jeolla Province. It 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).Photograph: Robert Simmon