To accomplish this, a plan was made to undertake construction of the 450 kilometers line, 북부철길 전철화, 동아일보, 1992 January 30 to be called the Pukpu Line in three stages: Manp'o–Hyesan, Hyesan–Musan, and Musan–Hoeryŏng, making use of existing rail lines where possible - including conversion of narrow gauge lines, and building new lines where necessary.