Jeju province encompasses the South Korean island of Jeju in the Korea Strait. It's known for its beach resorts and volcanic landscape of craters andcavelike lava tubes. Hallasan Mountain, a dormant volcano, features hiking trails, a crater lake at the 1,950m summit and nearby Gwaneumsa Temple. The Geomunoreum Lava Tube System includes 7km-long Manjanggul Cave, created centuries ago when Hallasan was still active.There’s plenty on Jeju-do to appeal to those who prefer to be active. Hike up South Korea’s highest mountain, Halla-san, or climb the incredible tuffcone Seongsan Ilchul-bong, rising straight from the sea, to watch the sun rise from the ridge of a crater. For a less-demanding nature experience,meander along one of the Jeju Olle Trails and explore tangerine-trimmed country roads, jagged coasts and narrow lanes dotted with cottage-style homesmade from black lava rock. The ocean is never far away, so plunge into blue seas to view coral as colourful as the sunsets and dig into Jeju-do’s uniquecuisine, including seafood caught by haeneyo (female free divers).