Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. German submarine U-186 - German submarine U-186 was a Type IXC/40 U-boat of Nazi Germany's Kriegsmarine built for service during World War II.Her keel was laid down on 24 July 1941 by AG Weser in Bremen as 'werk' 1026. She was launched on 11 March 1942 and commissioned on 10 July with Korvettenkapitan Siegfried Hesemann in command.The U-boat's service began with training as part of the 4th U-boat Flotilla. She then moved to the 10th flotilla on 1 January 1943 for operations.
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Mean Of Transportation