, ▁the ▁Supreme ▁Council ▁for ▁National ▁Re const ruction ▁started ▁South ▁Korea ' s ▁first ▁five - year ▁plan , ▁which ▁included ▁a ▁construction ▁program ▁to ▁complete ▁the ▁railway ▁network , ▁to ▁fost er ▁economic ▁growth . ▁As ▁part ▁of ▁the ▁program , ▁in ▁the ▁out sk ir ts ▁of ▁Se oul , ▁a ▁ ▁long ▁avoid ing ▁line ▁was ▁built ▁from ▁K w ang wo on ▁University ▁to ▁M angu ▁on ▁the ▁Jung ang ▁Line , ▁called ▁the ▁M angu ▁Line , ▁which ▁opened ▁on ▁December ▁ 3 0 , ▁ 1 9 6 3 . ▁ ▁Up grade ▁ ▁The ▁section ▁of ▁the ▁G ye ong won ▁Line ▁in ▁the ▁Se oul ▁metropol itan ▁area ▁was ▁among ▁the ▁first ▁to ▁be ▁elect r ified ▁with ▁the ▁ 2 5   k V / 6 0   Hz ▁AC ▁c aten ary ▁system ▁in ▁South ▁Korea ▁when ▁to ▁allow ▁for ▁through ▁train ▁services ▁with ▁Se oul ▁Sub way ▁Line ▁ 1 . ▁Further ▁sections ▁were ▁elect r ified ▁and ▁urban ▁services ▁to ▁Line ▁ 1 ▁was ▁extended ▁in ▁the ▁ 1 9 8 0 s ▁and ▁then ▁in ▁the ▁ 2 0 0 0 s : ▁ ▁Alt ogether ▁ ▁of ▁the ▁line ▁was ▁elect r ified , ▁and ▁ ▁was ▁double - track ed . ▁ ▁On ▁September ▁ 1 , ▁ 2 0 1 0 , ▁the ▁South ▁Korean ▁government ▁announced ▁a ▁strateg ic ▁plan ▁to ▁reduce ▁travel ▁times ▁from ▁Se oul ▁to ▁ 9 5 % ▁of ▁the ▁country