[1] The first section of mainline to be electrified by Sentetsu was also along the Gyeongwon Line, with the Pokkye−Gosan section being energised on 27 March 1944,[2] as part of a plan made jointly with the South Manchuria Railway for an electrified railway all the way from Busan to Xinjing, capital of Manchukuo.

[3] After the partition of Korea following the end of the Pacific War in 1945, the Gyeongwon Line was split along the 38th parallel between the stations of Hantangang and Choseongni.

[1] Following the 1961 coup, the Supreme Council for National Reconstruction started South Korea's first five-year plan, which included a construction program to complete the railway network, to foster economic growth.

[1] On September 1, 2010, the South Korean government announced a strategic plan to reduce travel times from Seoul to 95% of the country to under 2 hours by 2020.

[8] On December 16, 2023, a single-line railway between Soyosan and Yeoncheon opened on the Seoul Metropolitan Subway Line 1.