SM U-121
SM "U-121 was a Type UE II long-range minelaying U-boat of the Imperial German Navy intended for service in the Mediterranean. The Austro-Hungarian Navy allocated her the number SM "U-84. She was built at Hamburg, Germany, by Aktiengesellschaft Vulcan and launched on 20 September 1918. Incomplete at the Armistice she was never commissioned in the Imperial German Navy but surrendered to the Allies at Harwich on 9 March 1919. Handed over to France, she was sunk as a gunnery target off Cherbourg on 1 July 1921.