Haean Basin (Gangwon Peace Region National Geopark)

Haean Basin is an erosional basin in Korea formed by differential erosion. The high mountains outside the basin consist of metasedimentary rocks, while the low-lying areas are composed of Mesozoic granite. Cracks formed at the boundary between the metamorphic rocks and granite allowed water to seep through, breaking down the granite and creating a concave bowl shape. The place name Haean originates from the meaning that raising pigs caused the many snakes to disappear, bringing peace to the village. During the Korean War, UN forces called it the Punchbowl, inspired by the basin's unique shape.