Chatancheon, which flows from north to south along the Cheoryeong Gujo-gok, is a regional river that originates in the valley of Dokdoang-ri of Geumhaksan Mountain in Cheorwon and flows through a total length of 36.8km. Joins Hantan River in Jeongok.
Chatancheon Eumgil is a section of about 9.9km from Yeoncheon-eup to Jeongok-eup, and is a great place to appreciate the columnar joints of lava gorge with clean water. Chatancheon is the oldest pre-Cambrian period granite gneiss on the planet, from the Cretaceous fold movement, the gravel sedimentary layer (Baekui-ri layer) deposited by river movement in the early Cenozoic period, to the columnar joint formed by volcanic activity in the late Cenozoic period. Because it is a place that can be used, it can be said that it has excellent academic value. In addition, very important geoscientific points such as plains, grains, columnar joints, plate joints, lava dams, V-shaped gorges, waterfalls, vertical cliffs, and the Baekuiri Formation that cannot be easily seen in other rivers are scattered everywhere. All of these places are easily accessible along the Eum-gil, so they have an indispensable condition for tourists who want to explore the geology.