Jeju Island

Jeju Island is South Korea's most visited domestic destination, welcoming a staggering 12 million more annual visitors than runner-up Geojedo. It is the country's only UNESCO Triple Crown site—Natural World Heritage, Biosphere Reserve, and Geopark—a testament to its volcanic origin, subtropical climate, and unique biodiversity. The Hallasan volcano, rising 1,947 meters, dominates the landscape, while the island is famous for its haenyeo female divers, black lava beaches, and mandarin orange orchards. Unlike the mainland's temperate zone, Jeju's subtropical environment supports flora found nowhere else in Korea, making it a natural laboratory and top travel draw.