The German Maritime Museum (German: Deutsches Schifffahrtsmuseum (DSM)) is a museum in Bremerhaven, Germany. It is part of the Gottfried Wilhelm Leibniz Scientific Community. The main museum building was opened on 5 September 1975 by then-president of Germany Walter Scheel, though scientific work already had started in 1971. In 2000, celebrating the 25th anniversary of the museum, the Hansekogge, a ship constructed around 1380 that was found in the Weser river in 1962, was presented to the public after having undergone a lengthy process of conservation in a large preservative-filled basin.