The Italian battleship Duilio, also known as Caio Duilio, was an Andrea Doria-class vessel with significant service history spanning both World Wars. Constructed at the Regio Cantieri di Castellammare di Stabia, she was laid down in February 1912, launched in April 1913, and completed in May 1915. Originally, she measured 176 meters (577 feet) in length, with a beam of 28 meters (92 feet), a draft of 9.4 meters (31 feet), and a displacement of up to 24,715 metric tons at full load. Her hull featured a forecastle deck extending a third of the ship, with a superstructure comprising a small armored conning tower forward of the main gun turrets and a secondary tower aft. The ship's armament initially included thirteen 305 mm (12-inch) guns in three triple and two twin turrets, complemented by sixteen 152 mm (6-inch) guns, and anti-aircraft and torpedo armament. Her armor protection was substantial, with a belt of 254 mm (10 inches), a main deck of 98 mm (3.9 inches), and main battery turrets protected by 280 mm (11 inches) of Krupp steel. In the late 1930s, Duilio underwent an extensive reconstruction at Genoa, which increased her length to 186.9 meters (613 feet) and her displacement to 28,882 tons. Her machinery was upgraded with eight oil-fired boilers driving four Parsons turbines, boosting her top speed from 21 to 26 knots and extending her cruising radius to 4,800 nautical miles at 10 knots. Her armament was also modernized, replacing her main guns with ten 320 mm (13-inch) guns, and her secondary and anti-aircraft batteries were significantly improved. During her service, Duilio saw limited action in World War I due to the Austro-Hungarian fleet's inactivity. She participated in Mediterranean patrols, the Corfu incident of 1923, and deployments supporting Italian interests in Turkey and the Black Sea. She was involved in the 1925 Corfu occupation following the Greek incident, and later served as the flagship of the Italian fleet post-World War II. Notably, during World War II, she was damaged in the November 1940 Taranto air raid by British torpedo bombers, which tore a large hole in her hull. She was repaired and returned to service, participating in convoy escort missions and fleet operations, including the First Battle of Sirte. Her career was hampered by fuel shortages, and she was eventually placed in reserve after Italy's surrender in 1943, being interned at Malta and later returned to Italian ports. Duilio remained in service through the post-war period, serving as a fleet flagship until 1949, before being moved to La Spezia and stricken from the naval register in 1956. She was sold for scrapping in 1957, marking the end of a notable naval career that spanned over four decades.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.