Paektusan Chongnyon Line

This line traverses a very mountainous area; it has a ruling grade of 33‰ and a minimum curve radius of 250 metres. There are 74 bridges totalling 2,175 m (7,136 ft) and 24 tunnels with a total length of 8,398 m (27,552 ft). The average distance between stations is 7.1 km (4.4 mi). Service facilities on the line are at Hyesan for locomotives and at Wiyŏn and Paeg'am for rolling stock.[2]

In order to exploit the Paektusan region's abundant forest and mineral resources, the Yanggang Forest Development Railway planned construction of a line, dubbed Hambuk Line, running from Kilju to Hyesanjin (now Hyesan Ch'ŏngnyŏn) via Hapsu, along with a branch from Hapsu to Komusan, already at the beginning of the 1920s. The Yanggang Forest Development Railway was one of six privately owned railway companies that merged to create the Chosen Railway on 1 September 1923,[3] but work on the planned line was not started before the Chosen Government Railway (Sentetsu) took over the project. Sentetsu finally began construction of the line in May 1931, with the first section, 57.2 km (35.5 mi) from Kilju to Hapsu, being opened on 1 November 1933.[4] The line was then extended several times over the following four years: 12.8 km (8.0 mi) from Hapsu to Paegam was opened on 1 August 1934[5] and 29.7 km (18.5 mi) from Paegam to Pongduri (now Unhŭng) on 1 September 1935, and the final 42.0 km (26.1 mi) from Pongduri to Hyesanjin was completed on 1 November 1937.[6][7]

Originally called the Kilhye Line (from the names of the two termini, Kilju and Hyesan), the line received its present name in 1978,[8] when electrification of the line was completed in September of that year.[2]

The planned Komusan–Musan section, using the Hambuk Line name, was finally opened in 1937 by the North Chosen Colonial Railway (a subsidiary of the Chosen Railway),[9] whilst the section between Musan and the Kilhye Line (at Paegam instead of Hapsu as had been planned and named Paengmu Line) was finally completed as a narrow gauge railway by Sentetsu on 1 December 1944.[10]

When the Pukbunaeryuk Line was completed to Hyesan in 1988, a northern east-west connection was finally established connecting the Manp'o Line at Manp'o Ch'ŏngnyŏn to the Paektusan Ch'ŏngnyŏn Line.

On 9 October 2006 an underground nuclear test was conducted at Punggye-ri Nuclear Test Site in Kilju County, causing the closure of the line for 3-4 months after the Paegam tunnel, near Paegam Ch'ŏngnyŏn station, collapsed.[11]

A yellow background in the "Distance" box indicates that section of the line is not electrified.