The Oberbaumbrücke over the Spree river is Berlin's most iconic bridge, connecting the now-combined boroughs of Friedrichshain and Kreuzberg. It carries vehicles, pedestrians, and the U1 Berlin U-Bahn line. The bridge was completed in a brick gothic style in 1896, replacing the former wooden bridge with an upper deck for the U-Bahn. The center portion was demolished in 1945 to stop the Red Army from crossing. After the war, the repaired bridge served as a checkpoint and border crossing between the Soviet and American sectors, and later between East and West Berlin. In the mid-1950s, it was closed to vehicles, and after the construction of the Berlin Wall in 1961, pedestrian traffic was heavily restricted. Following German reunification, the center portion was reconstructed with a steel frame, and U-Bahn service resumed in 1995.