▁railway ▁network ▁was ▁at ▁the ▁heart ▁of ▁Germany ' s ▁Light ning ▁war ▁strategy ▁to ▁attack ▁France ▁through ▁Belg ium . ▁After ▁the ▁war ▁on ▁the ▁western ▁front ▁st agger ed ▁to ▁a ▁military ▁st alem ate , ▁the ▁cross ▁border ▁Ham mer ▁Bridge ▁route ▁incorpor ating ▁the ▁Ham mer ▁Bridge ▁remained ▁critical ▁both ▁for ▁supp lying ▁fresh ▁troops ▁and ▁m un itions ▁to ▁the ▁western ▁front , ▁and ▁for ▁the ▁return ▁home ▁of ▁cas ual ties ▁and ▁exha usted ▁troops . ▁In ▁ 1 9 1 5 ▁work ▁began ▁on ▁a ▁second ▁route ▁across ▁the ▁front ier ▁with ▁Belg ium , ▁crossing ▁the ▁Ge ul ▁a ▁few ▁kilometres ▁to ▁the ▁west ▁at ▁M ores net , ▁in ▁order ▁to ▁make ▁the ▁log istics ▁of ▁the ▁military ▁operation ▁less ▁vulner able ▁to ▁con g estion ▁at ▁and ▁around ▁the ▁old ▁front ier ▁station ▁at ▁Her best hal . ▁After ▁the ▁war ▁ended ▁in ▁ 1 9 1 8 , ▁the ▁vict orious ▁powers ▁im posed ▁a ▁front ier ▁change ▁where by ▁E up en - Mal med y , ▁a ▁strip ▁of ▁land ▁between ▁A achen ▁and ▁Luxemb ourg , ▁was ▁transferred ▁from ▁Germany ▁to ▁Belg ium . ▁The ▁amount ▁of ▁land ▁involved ▁was ▁only ▁ 1 , 0 3 6 ▁km ² ▁( rough ly ▁ 5 % ▁of ▁the ▁size ▁of ▁Wales , ▁or ▁less ▁than ▁half ▁the ▁size ▁of ▁Long ▁Island ) ▁but ▁it ▁included ▁the ▁piece ▁of ▁main line ▁railway ▁incorpor ating ▁the ▁Ham mer ▁Bridge , ▁which ▁would