Kosan County is a kun, or county, in Kangwŏn province, North Korea. The county is predominantly mountainous, with a central basin. Its highes…Kosan County is a kun, or county, in Kangwŏn province, North Korea. The county is predominantly mountainous, with a central basin. Its highest point is Chuaesan. Major streams include the Namdaech'ŏn, Ryongjiwŏnch'ŏn, and Namsanch'ŏn. The county contains 13 reservoirs, and Forestland covers approximately 63.8% of its area.