Olympiastadion is a railway station in the Westend district of Berlin. Located at the southern entrance of the Olympic Stadium, it is served by the S-Bahn lines S3 and S9. The station consists of one island platform which is in regular use, as well as four further terminal island platforms which are only used for the extra trains during major events. The station opened in 1909 on the Westbahn suburban railway north of the Grunewald forest.