USS Iowa (BB-53), a battleship already under construction when she was canceled by the Washington Naval Treaty
USS Iowa (BB-61), the lead ship of the Iowa-class battleships that saw action during World War II and the Korean War
USS Iowa (SSN-797), a planned Virginia-class submarine
Iowa (steamboat), 1838, a Mississippi River boat that transported troops during the Civil War
Non-military vessels named Iowa
SS Iowan
A stern-wheel rafter/packet named Iowa plied the Mississippi 1865-1900.
A stern-wheel towboat named Iowa operated in the Mississippi 1921-1954; a contemporaneous dredge named Iowa also existed 1932-1956.
An ocean-going steamer named Iowa was in use in the late 19th century.
In 1898 an excursion steamboat named Iowa was launched in Independence, Iowa, after several years as a popular attraction, it was carried over the Independence dam by high water and was demolished.
