An >100 year ship still in active duty naval use:<p><i>Kommuna is a submarine salvage ship in service with the Russian Navy's Black Sea Fleet and the world's oldest active duty naval vessel.[2] A double-hulled catamaran, she was laid down at the Putilov Factory (now the Kirov Factory) in St. Petersburg in November 1912 as Volkhov. The ship was launched the following year, and commissioned on 14 July 1915. She was renamed Kommuna on 31 December 1922. Kommuna has served in the Russian Imperial, Soviet, and Russian Federation navies through the Russian Revolution and two World Wars.</i><p><a href="https://en.wikipedia.org/wiki/Russian_salvage_ship_Kommuna" rel="nofollow">https://en.wikipedia.org/wiki/Russian_salvage_ship_Kommuna</a>