Jeju-do (Jeiju Island) is the most popular tourist destination of the people of South Korea. It is located 485 km south of Seoul, 100 km off the coast of the mainland at the southern cape of the Korean peninsula.
Jeju-do has three lava tubes which are open to the public. The Songsan Ilch'ulbong Peak (Sunrise Peak), 48 km east of Jeju City, is a 182 m high volcano.
In 2010 nine geological sites in Jeju Island were designated as world geoparks by UNESCO's Global Geopark Network of National Geoparks (GGN). This includes Manjanggul Cave. The island already has a UNESCO Biosphere Reserve recognition and several Natural Heritage Sites, which also includes Manjanggul. Jeju is planning to provide geology education to the general public on the recognized sites.