Since the distance between South Sinŭiju and Namsi via the Yangsi Line was nearly 11 kilometers shorter than via the original routing of the P'yŏngŭi Line via Paengma, Kukch'ŏl decided to rearrange the lines; thus, the Yangsi Line was made part of the P'yŏngŭi Line, and the original South Sinŭiju–Paengma–Yangsi section was separated to become the Paengma Line in 1964.