The privately owned Tanp'ung Railway was formed to build a railway from Tanch'ŏn on the Hamgyŏng Line of the Chosen Government Railway to P'ungsan, the county seat of P'ungsan County; it was from the first characters of the names of the endpoints that the railway, and the mainline, got its name. The initial section of the mainline, 80.3 km (49.9 mi) from Tanch'ŏn to Honggun, was opened on 26 August 1939.[2] A branchline, the Mandŏk Line, from Kosŏng (now called Hŏch'ŏn) to Mandŏk was also opened, but the planned continuation from Honggun to P'ungsan was not completed before the fall of Japan at the end of the Pacific War.
Following the partition of Korea, the entirety of the Tanp'ung Railway's network was located in the Soviet zone of occupation. The Provisional People’s Committee for North Korea nationalised all railways in the northern half of the country on 10 August 1946, and following the establishment of North Korea, the Korean State Railway was created.[3] Damage sustained by the line during the Korean War was repaired and the line was eventually electrified, but the extension to P'ungsan (renamed Kimhyŏnggwŏn in 1990) was never built.