Finnish submarine Vesikko

Vesikko is a submarine, which was launched on 10 May 1933 at the Crichton-Vulcan dock in Turku. Until 1936 it was named by its yard number CV 707. Vesikko was ordered by a Dutch engineering company Ingenieurskantoor voor Scheepsbouw in 1930 as a commercial submarine prototype, being the prototype for the German Type II submarines. Purchased by the Finnish before World War II, she saw service in the Winter War and Continuation War, sinking the Soviet merchant ship Vyborg as her only victory. After the cease-fire with the Allies in 1944, Vesikko was retired. Finland was banned from operating submarines after the war and she was kept in storage until she was turned into a museum ship.

Vesikko was one of five submarines to serve in the Finnish Navy. The other four were the three larger Vetehinen-class boats Vetehinen, Vesihiisi, Iku-Turso and the small Saukko. The word "vesikko" is the Finnish name for the European mink.