After World War II , the Stadtbahn lay devastated by bombs , but was rebuilt very quickly . Because Joseph Stalin wanted to travel by train to the Potsdam Conference , the Stadtbahn was converted to the Russian broad gauge in 1945 . The national importance had diminished with the loss of eastern Germany ; only a few trains ran towards the western zones . Some trains from the Soviet zone terminated on the Stadtbahn
Potsdam Conference
Potsdam Conference
Berlin Stadtbahn