Sundamgyegok Valley (순담계곡)

Sundamgyegok Valley is a scenic valley along the Hantangang River in Cheorwon, Gangwon, set inside the broader UNESCO Hantangang River Geopark area near the inner Korean border. The valley features striking columnar-basalt cliff formations along the river — a defining geological signature of the Hantangang Geopark — alongside clear-water river-bed sections, walking paths, viewing decks, and the famous Sundam swing-bridge crossing the river. The combination of dramatic basalt cliffs, the clear river water, and the surrounding mountain-and-forest landscape makes Sundamgyegok one of the Hantangang Geopark's most-cited landscape destinations. Best in summer for the strongest water flow and cooler atmosphere, paired with broader Hantangang Geopark itineraries including Bidulginangpokpo Falls.