Ten years after the advent of the first domestic car, the 1960s witnessed a sudden increase in the number of cars and buses in Korea. In Seoul in 1970, with a population that already exceeded five million, the construction of a subway line was the only solution available to relieve the intense traffic congestion of the downtown area.
Throughout the 1960s, numerous plans were drawn up for the construction of a subway system, but it was in 1970, with the appointment of Mayor Yang Taek-sik (former director of the Korean National Railroad), that the plan was actually put into action. On April 12, 1971, a ceremony was held, with over 30,000 citizens in attendance, to mark the beginning of the construction of Subway Line 1. On August 15, 1974, the day of the historic opening of the third subway line in Asia, First Lady Yuk Yeong-su was shot and killed by an assassin at a National Liberation Day event. This resulted in the cancellation of all other events other than the subway line opening event. At the time of its opening, the basic subway fare from Seoul Station to Cheongnyangni was KRW 30. The subway ticket, which today costs KRW 1,050, has since undergone numerous changes.