The Gleinicker Brücke (or Gleinicke bridge) is located in the south western part of Berlin, spanning over the Havel river, conntecting Berlin to Potsdam. The currently standing structure comes from 1907 and it the fourth one on its place.
The Gleinicke bridge has played a very important role during the cold war, being located right at the border between the Soviet block and the West. Due to its frequent use a place of exchanging captured personnel on both sides, it has become known as the Bridge of Spies (also the name of a Tom Hanks movie, where the bridge also plays a role)
The bridge was partly destroyed during the World War II during the fighting between Wehrmacht and the Red Army, and wasn’t rebuilt until 1949, when it faced two competing block on each side – The East backed by Russia and the West by the USA.
At the beginning of the Cold War the brigde was freely used, alhough mostly by the military personnel on both sides, as the movement of people maintained free between the East and West Germany. In 1952, the East German gocernment decided to close the bridge (called the Unity Bridge in DDR) for the West Berliners. The East Berliners were allowed to use it untill the erection of the Berlin wall in 1961.
The bridge was opened to the public on both sides in 1989, one day after the fall of the Berlin Wall.
See my other entries on Soviet/East Germany remnants in Berlin:
War Memorial in Treptow: https://seeinberlin.com/2016/01/27/sovieteast-germany-remnants-1-soviet-world-war-ii-memorial-in-treptow/
War Memorial in Pankow: https://seeinberlin.com/2016/07/05/sovieteast-germany-remnants-2-soviet-world-war-ii-memorial-in-pankow/
Alexanderplatz pt1: https://seeinberlin.com/2016/02/22/alexanderplatz-part-1-east-germany-remnants-main-berlin-landmarks/