▁construction ▁of ▁the ▁Back n ang - B iet ig heim ▁line ▁was ▁sought ▁by ▁the ▁national ▁government ▁for ▁military - str ateg ic ▁reasons . ▁In ▁B iet ig heim ▁a ▁connection ▁had ▁previously ▁been ▁planned ▁north ▁of ▁the ▁station , ▁which ▁would ▁have ▁meant ▁that ▁trains ▁running ▁in ▁an ▁east – west ▁direction ▁would ▁have ▁had ▁to ▁reverse ▁in ▁the ▁station . ▁To ▁allow ▁troops ▁to ▁be ▁speed ily ▁transport ed ▁in ▁the ▁east – west ▁direction ▁from ▁northern ▁Bav aria ▁to ▁the ▁French ▁border , ▁the ▁plans ▁were ▁adjust ed ▁so ▁that ▁the ▁line ▁ran ▁in ▁a ▁curve ▁from ▁the ▁south ▁to ▁reach ▁B iet ig heim ▁station ▁via ▁an ▁under pass ▁under ▁the ▁railway ▁from ▁Stuttgart . ▁Since ▁the ▁entrance ▁building ▁was ▁built ▁on ▁an ▁island ▁between ▁the ▁tracks ▁of ▁the ▁Northern ▁and ▁Western ▁Railway , ▁a ▁complete ▁renov ation ▁of ▁B iet ig heim ▁station ▁was ▁considered . ▁ ▁With ▁the ▁imp ending ▁agreement ▁to ▁build ▁the ▁Kra ich g au ▁Railway ▁between ▁E pping en ▁and ▁Heil br onn , ▁Wür ttemberg ▁was ▁faced ▁with ▁an ▁unf av ou rable ▁situation ▁in ▁that ▁the ▁Kra ich g au ▁and ▁the ▁Koch er ▁Railway ▁were ▁emer ging ▁as ▁a ▁new ▁transport ▁cor rid or ▁between ▁the ▁Rh ine ▁and ▁Bav aria , ▁with ▁only ▁a ▁relatively ▁short ▁section ▁through ▁Wür ttemberg . ▁The ▁planned ▁M urr ▁Valley ▁Railway ▁would ▁be ▁compet itive ▁with ▁this ▁route ▁if ▁an ▁additional ▁northern ▁by pass ▁was ▁built ▁around ▁the ▁highly ▁con g