- Lonely Planet Korea is your passport to all the most relevant and up-to-date advice on what to see, what to skip, and what hidden discoveries await you. Walk along Cheong-gye-cheon"s long-buried stream, hike around Jeju-do"s volcanic landscape, or jump into a vat of mud during the Boryeong Mud Festival; all with your trusted travel companion. Get to the heart of Korea and begin your journey now!