The Kaech'ŏn–Ch'ŏndong section was originally a 762 mm narrow gauge line opened on 1 December 1918 by the Mitsui Mining Railway (미츠이 광산 전용 철도, Mich'ŭi Kwangsan Chŏn'yong Ch'ŏldo; 三井鉱山専用鉄道, Mitsui Kōzan Sen'yō Tetsudō) as an extension to its Sinanju–Kaech'ŏn mainline; in 1927 the company was renamed Kaech'ŏn Light Railway (개천 경변철도, Kaech'ŏn Kyŏngbyŏn Ch'ŏldo ; 价川軽便鉄道, Kaisen Keibentetsudō), and then was leased to the Chosen Government Railway (Sentetsu) on 1 November 1932.