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Potsdam-Griebnitzsee station is an S-Bahn station in Potsdam on the outskirts of Berlin in the German state of Brandenburg. The station is located in the east of the Babelsberg suburb of the city of Potsdam in the state of Brandenburg, and about 600 metres (2,000 ft) outside the Berlin city boundary. It takes its name from the adjacent Griebnitzsee lake. It is on the Wannsee Railway. During the division of Germany, it served as a border station for traffic to West Berlin. The station is now served by trains on line S7 of the Berlin S-Bahn and Regionalbahn services RB 21 and RB 22. It is classified by Deutsche Bahn as a category 4 station.