Trento - class cruiser The " Trento " class was an Italian heavy cruiser design of the " Regia Marina " from the late 1920s . The three ships in the class were named after the three unredeemed cities taken from the Austro - Hungarian empire after the victory in World War I : Trento , Trieste , and Bolzano . The " Trentos " were the first ships designed specifically to the limitations of the Washington Naval Treaty . This limited cruisers to 10 , 000 tons and 8 inch ( 203 mm ) guns , a limitation that made firepower , speed and protection difficult to build into a single design . A particular problem faced by the Italian designers was that their ships had to be able to protect the lengthy Italian coastline from widely separated naval bases , meaning that high speed was a key feature . In the end they chose to sacrifice armor and fuel storage , and thus range , in order to attain the required speed and weight while still being armed with the latest 8 inch ( 203 mm ) guns . " Trento " started construction in 1925 along with her sister ship , " Trieste " . " Trieste " was launched first in 1926 and commissioned in 1928 , while " Trento " followed in 1927 and 1929 respectively . A third , " Bolzano " , started construction in 1930 and was commissioned in 1933 ; the " Bolzano " was quite different from the other two vessels , and sometimes it is considered a class on its own . It was later concluded that the tradeoff in armour put the ships at a disadvantage , and an up - armored version of the design was produced as the highly rated " Zara " class in the early 1930s . The three warship constituted Italian Navy ' s Third Division of cruisers . " Trieste " . Trieste served as the flagship of the 3rd Division . In 1940 , she participated in the battle of Cape Spartivento . At Spartivento , the three cruisers of the class fired on their British counterparts from a range of 21500 yards ( over 12 miles ) , and it is believed that either " Trieste " or " Trento " hit the heavy cruiser HMS " Berwick " twice and straddled HMS " Manchester " . On 21 November 1941 she was hit by a torpedo from the submarine HMS " Utmost " , and although badly damaged , she was able to reach base at Messina with difficulty . She remained out of action until mid - 1942 , when she rejoined the fleet . On 10 April 1943 , she sank after being hit by several bombs dropped by USAAF B - 24 s while in port at La Maddalena , Sardinia . After the war , she was sold to Spain in 1951 , being raised and moved to Ferrol in anticipation of being converted into an aircraft carrier , but a change in leadership of the Spanish Navy saw the project being dropped , and the cruiser was scrapped . " Trento " . In June 1929 , Trento began a cruise to South America which extended until 10 October 1929 . In February 1932 " Trento " was sent to Tianjin , China , to join the " San Marco Battalion " as a show of force during the Second Sino - Japanese War , returning on 30 June . In August 1933 , " Trento " joined the " Trieste " and newly commissioned " Bolzano " to become the Second Naval Division . In 1934 the " Regia Marina " was re - organized , and the three ships became the Third Naval Division . During the Spanish Civil War the division carried out escort missions in the western Mediterranean Sea . During World War II , " Trento " took part in most major Italian operations , including the battles of Calabria , Cape Spartivento , and Cape Matapan . On the morning of 15 June 1942 " Trento " was navigating in a battle fleet to prevent a large Allied convoy from reaching Malta ( Operation " Vigorous " ) , and was attacked and sunk after being torpedoed twice . The first hit was inflicted by a Malta - based Bristol Beaufort bomber at 5 : 15am . This plane was flown by f / o Arthur Aldridge and his crew . This operation was later recalled in his book ' The Last Torpedo Flyers ' published in 2013 . " Trento " was immobilized and left behind , assisted by the destroyer " Da Verrazzano " , while the rest of the fleet continued south in pursuit of the " Vigorous " convoy . The Royal Navy submarine HMS " Umbra " found the smoking ship at 9 : 10am , and torpedoed her hitting the magazine , sinking the " Trento " rapidly ( 9 : 15am ) . Crew members had little time to put on life vests and abandon ship . Over half the crew died from the explosions , went down with the ship or were killed when Italian escort ships dropped depth charges to stop the submarine . " Trento " still lies at the bottom of the Ionian Sea , where the Mediterranean is at its deepest , at the position . " Bolzano " . Bolzano was built a year later than the other two , with enough differences that she is sometimes considered a separate class . She served in most of the same missions as her sisters . She was hit three times by six - inch rounds from the British cruiser HMS " Neptune " in the battle of Calabria , where she sustained two deaths and minor damage below the waterline , which was patched up in just six minutes . Another round hit in the " B " turret and holed the guns , which continued to fire undeterred . A third round struck the torpedo room , where the two fatalities took place . At the beginning of the battle of Spartivento , her Ro . 43 floatplane was the first to spot the British fleet 20 miles off Algeria . On 25 August 1941 , while returning from an abortive attempt to intercept minelayer HMS " Manxman " , used by the British in re - supply missions , " Bolzano " was damaged by a torpedo from the British submarine HMS " Triumph " near the Straits of Messina . With her steering damaged , she had to be towed to Messina . Repairs lasted three months , during which she was hit during an air raid . In August 1942 , when her participation in the interception of the " Pedestal " convoy had been cancelled , she was again torpedoed while returning to base . " Bolzano " and the light cruiser Muzio Attendolo were both seriously damaged by torpedoes from the British submarine HMS " Unbroken " off the Aeolian Islands on 13 August . The damage to " Bolzano " required her magazine s to be flooded and she was beached at the island of Panarea . After a month , she was salvaged and taken first to Naples , then to La Spezia for repairs . While she was at La Spezia in September the Italians surrendered and she was captured by the Germans . However the damage was so heavy that they didn ' t have resources to repair her . She was sunk by former members of Decima Flottiglia MAS , transported by human torpedoes , in a combined Italian and British raid on 21 June 1944 . After the war she was refloated , and sold for scrap in 1947 .