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The Kanggye Line was built by the Korean State Railway in the late 1940s to aid in the construction of a hydroelectric dam on the Changjin River in the Rangrim mountains; construction of the dam had been started by the Japanese in 1937. Following an order issued in September 1999 by Kim Jong-il, electrification of the line at 1500 V DC was completed on 5 October 2000.
Route
A yellow background in the "Distance" box indicates that section of the line is not electrified; a pink background indicates that section is 2 ft 6 in (762 mm) narrow gauge; an orange background indicates that section is non-electrified narrow gauge.