경원선
Until the division of Korea following the end of the Second World War, the Gyeongui Line and Gyeongwon Line extended into what is now North Korea. The Gyeongui Line connected Seoul to Kaesong, Pyongyang, and Sinuiju on the Chinese border, while the Gyeongwon Line served Wonsan on the east coast. Another line—the Kumgangsan Electric Railway—connected the town of Cheorwon, now on the border of North and South Korea, on the Gyeongwon Line, to Mt. Geumgang, now in the North.