Height: 452 meters, Type: Shield vol­cano, Sta­tus: Holocene. Shield vol­cano 452 m. An area of exten­sive basaltic lava flows occu­pies a graben, the NNE-SSW-trend­ing Ch’u­ga-ryong rift, that cuts diag­o­nal­ly across the demil­i­ta­rized zone between North and South Korea. One 40-km-long lava flow orig­i­nat­ed from the low Ap-san shield vol­cano, which has a 200-m-wide sum­mit crater and more than 20 satel­litic cones. Anoth­er volu­mi­nous late-Pleis­­tocene lava flow is 60 km long. Alka­line basaltic lava flows at the SW por­tion of the rift were erupt­ed over Pre­cam­bri­an sed­i­ments and igneous rocks, and were esti­mat­ed by Lee (1981) to be late-Pleis­­tocene or ear­ly Holocene in age.