HSwMS Delfinen explained

Five warships of Sweden have been named Delfinen (Swedish for dolphins):

• , a warship launched in 1626.
• , a galley launched in 1713.
• , a submarine launched in 1914 and stricken 1930.
• , a Delfinen class submarine launched in 1934 and stricken in 1957.
• , a launched in 1961 and stricken in 1993.