▁the ▁line ▁cross es ▁the ▁E ider ▁river , ▁which ▁flows ▁into ▁the ▁K iel ▁Canal ▁nearby . ▁The ▁line ▁reaches ▁the ▁K iel – Fl ens burg ▁line ▁and ▁then ▁the ▁Hamburg - Al ton a – K iel ▁line ▁just ▁before ▁the ▁entrance ▁to ▁K iel ▁Haupt bahn hof . ▁ ▁History ▁ ▁Hus um - Er f de - R ends burg ▁ ▁On ▁ 1 ▁September ▁ 1 9 1 0 , ▁a ▁ 5 0   km - long ▁direct ▁Hus um – Er f de – R ends burg ▁line ▁opened . ▁It ▁ran ▁from ▁Hus um , ▁crossed ▁the ▁lower ▁Tre ene ▁river ▁to ▁N order st ap el ▁and ▁ran ▁via ▁Er f de ▁to ▁R ends burg ▁and ▁then ▁continued ▁on ▁the ▁current ▁route ▁to ▁K iel . ▁The ▁line ▁crossed ▁the ▁Schles wig ▁District ▁Railway ' s ▁line ▁between ▁Friedrich stadt ▁and ▁Schles wig ▁in ▁N order st ap el ▁until ▁ 1 9 3 4 . ▁ ▁In ▁the ▁late ▁ 1 9 2 0 s , ▁there ▁were ▁continuous ▁passenger ▁services ▁on ▁the ▁Hus um – Er f de – R ends burg – K iel ▁route , ▁with ▁a ▁total ▁running ▁time ▁of ▁about ▁three ▁hours . ▁A ▁few ▁faster ▁services ▁on ▁the ▁route ▁took ▁about ▁two ▁hours ▁and ▁ 2 0 ▁minutes . ▁In ▁ 1 9 5 9 , ▁motor ▁coach es ▁on ▁the ▁route ▁to ▁R ends burg ▁took ▁about ▁ 7 0 ▁minutes . ▁Local ▁trains