Submarine CV-707 was built by the Crichton-Vulcan shipyard (Turku) as a pilot sample for the German Navy. It was launched in 1933 and tested for two years.
In 1936 the submarine was bought by Finland and named 'Vesikko'. It was in service till 1946. In 1973 it was opened to public at Suomenlinna (Sveaborg) fortress
