Gyeongui Line (1904–1945)
Following Japan's defeat in the Pacific War and the subsequent partition of Korea, the Gyeongui Line was divided at the 38th parallel between North and South Korea. On 25 August 1945, the Soviet Army began operating trains on the line north of Sariwon, whilst trains in the south terminated at Gaeseong. In 1946, the railways in both North and South were nationalised, creating the Korean National Railroad in the South and the Korean State Railway in the North. After the Korean War, the Gyeongui Line was split into three sections. In the South, the Seoul–Jangdan section became the KNR's Gyeongui Line, retaining the same name; in the North, the Bongdong–Pyeongyang section became the P'yŏngbu Line, whilst the Pyeongyang–Sinuiju section became the P'yŏngŭi Line.
Gangwon Province, South Korea
In 1945 Gangwon-do (along with the rest of Korea) was divided by the 38th parallel north in 1945 into American and Soviet zones of occupation in the south and north respectively, which led to Wonsan joining the province's northern half in 1946 to serve as its administrative center. In 1948, the southern half of the province became part of the new Republic of Korea. As a result of the Korean War of 1953, the boundary between the South and North Korean portions of the province was shifted northward to the Military Demarcation Line.