Upgrade
The Gyeongbu Line was extensively upgraded in parallel with the development of the Seoul Metropolitan Subway urban rapid transit system and the Korea Train Express (KTX) high-speed rail system from the 1970s.
The Gyeongbu Line is six-tracked from Seoul to Guro, four-tracked from Guro to Cheonan, and double-tracked from Cheonan all the way to Busan. The entire line is electrified.
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