The Caio Duilio was an Italian Duilio Class dreadnought of 24500 tons displacement launched in 1913 and rebuilt in 1939 as a Cavour Class battleship of 23622 tons displacement. The Caio Duilio was powered by eight 3-drum type boilers providing a top speed of 27 knots and carried a complement of 1074 increased to 1198 after rebuilding. She was originally armed with thirteen 12-inch guns; sixteen 6-inch guns; thirteen 14 pdr guns, three of which were removed for the duration of the Great War; six 14 pdr anti-aircraft guns; two machine-guns and four 18-inch torpedo tubes. After reconstruction prior to the Second World War she was armed with ten 12.6 inch guns; twelve 5.3 inch guns; ten 3.5 inch anti-aircraft guns; thirty-nine anti-aircraft machine-guns and carried four aircraft. Research Caio Duilio