🌋💧Jeju Lava Seawater. A unique underground water resource of Jeju that contains rich mineralsand nutritive salts with no organic material or pathogens. • What is Jeju? 🌴Jeju-do (제주도), Korea’s largest island. The one of the most relaxing vacation spots found in Korea thanks to its unique local atmosphere and beautiful natural environment. The volcanic lava tubes that make up nearly 10% of the island’s area are a designated UNESCO World Natural Heritage Site. Jeju Island is the largest offshore island of the Korean peninsula and is about a 1 hour flight away from Seoul. Best known for its beautiful volcanic landmarks, white sand beaches and of course, the Jeju Black Pork dishes and green tea plantations, you’ll get to feast your eyes and fill your bellies all in one place!