U-129 may refer to one of the following German submarines:
Germany, officially the Federal Republic of Germany, is a country in Central and Western Europe, lying between the Baltic and North Seas to the north, and the Alps to the south. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, France to the southwest, and Luxembourg, Belgium and the Netherlands to the west.
- SM U-129, a Type U 127 submarine laid down during the First World War but unfinished at the end of the war; broken up incomplete 1919–20
- During the First World War, Germany also had this submarine with a similar name:
- SM UB-129, a Type UB III submarine launched in 1918 and scuttled on 31 October 1918
SM UB-129 was a German Type UB III submarine or U-boat in the German Imperial Navy during World War I. She was commissioned into the German Imperial Navy on 11 June 1918 as SM UB-129.
The Type UB III submarine was a class of U-boat built during World War I by the German Imperial Navy.
- During the First World War, Germany also had this submarine with a similar name:
- German submarine U-129 (1941), a Type IXC submarine that served in the Second World War until taken out of service on 4 July 1944; scuttled on 18 August 1944; raised and stricken in 1946; broken up. U-129 sank the Mexican tankers SS Tuxpam and SS Las Choapas in June 1942 under Captain Hans-Ludwig Witt.
Type U 127 submarine was a class of U-boats built during World War I by the Kaiserliche Marine.
Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship.
World War I, also known as the First World War or the Great War, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918. Contemporaneously described as "the war to end all wars", it led to the mobilisation of more than 70 million military personnel, including 60 million Europeans, making it one of the largest wars in history. It is also one of the deadliest conflicts in history, with an estimated nine million combatants and seven million civilian deaths as a direct result of the war, while resulting genocides and the 1918 influenza pandemic caused another 50 to 100 million deaths worldwide.
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