flagships in the southern Adriatic Sea during World War I, but saw no action and spent little time at sea. Leonardo da Vinci was also little used and was sunk by an internal magazine explosion at Taranto harbor on the night of 2/3 August 1916 while loading ammunition. Casualties included 21 officers and 227 enlisted men killed. The Italians blamed Austro-Hungarian saboteurs, but unstable propellant may well have been responsible. The ship was refloated, upside down, on 17 September 1919 and righted on 24 January 1921. The Regia Marina planned to modernize her by replacing her center turret with six AA guns, but lacked the funds to do so and sold her for scrap on 22 March 1923. In 1919, Conte di Cavour sailed to North America and visited ports in the United States as well as Halifax, Canada. Giulio Cesare made port visits in the Levant in 1919 and 1920. Conte di Cavour was mostly inactive in 1921 because of personnel shortages and was refitted at La Spezia from November to March 1922. Both battleships supported Italian operations on Corfu in 1923 after an Italian general and his staff were murdered on the Greco-Albanian border; Benito Mussolini was not satisfied with the Greek Government's response so he ordered Italian troops to occupy the island. Conte di Cavour bombarded the town with her 76 mm guns, killing 20 and wounding 32 civilians. Conte di Cavour escorted King Victor Emmanuel III and his wife aboard Dante Alighieri, on a state visit to Spain in 1924 and was placed in reserve upon her return until 1926, when she conveyed Mussolini on a voyage to Libya. The ship was again placed in reserve from 1927 until 1933. Her sister became a gunnery training ship in 1928, after having been in reserve since 1926. Conte di Cavour was reconstructed at the CRDA Trieste Yard while Giulio Cesare was rebuilt at Cantieri del Tirreno, Genoa between 1933 and 1937. Both ships participated in a naval review by Adolf Hitler in the Bay of Naples in May 1938 and covered the invasion of Albania in May 1939. Early in World War II, the sisters took part in the Battle of Calabria (also known as the Battle of Punta Stilo) on 9 July 1940, as part of the 1st Battle Squadron, commanded by Admiral Inigo Campioni, during which they engaged major elements of the British Mediterranean Fleet.