Bolzano had a fairly uneventful peacetime career, which primarily consisted of naval reviews for Italian and foreign dignitaries.

She also frequently escorted convoys to North Africa in 1941 and 1942 and patrolled for British naval forces in the central Mediterranean Sea.

After Italy surrendered to the Allies in September 1943, La Spezia was occupied by German forces; to prevent them from using her as a blockship, Italian and British frogmen sank Bolzano using Chariot manned torpedoes in June 1944.

Bolzano was ordered under the 1929–1930 construction program;[1] the Regia Marina had initially planned on building six heavy cruisers in the 1920s and 1930s, which comprised the Trento and Zara classes.

These vessels were to have operated as two three-ship cruiser divisions, but by 1929, the Regia Marina had decided to use Pola as a temporary fleet flagship while the Conte di Cavour-class battleships were being rebuilt.

[1] The high command of the Regia Marina persisted in their belief that speed was more important than armor, and so the new vessel adopted a level of protection similar to the earlier Trentos rather than the more sturdily built Zaras.

While on speed trials with a light displacement of 10,847 long tons (11,021 t), she reached 36.81 knots (68.17 km/h; 42.36 mph) from 173,772 shp (129,582 kW).

[1] The keel for Bolzano was laid down at Ansaldo's shipyard in Genoa on 11 June 1930, and her completed hull was launched on 31 August 1932.

The ship received her battle flag on 29 June 1934 at a ceremony held in the Grand Canal of Venice, in company with Trento.

[3] The ship steamed to the Balearic Islands to retrieve the bodies of six Italian sailors who had been killed on 25 May aboard the auxiliary cruiser Barletta by Republican bombers during the Spanish Civil War; Bolzano arrived back in Italy on 3 June.

Four days later, she took part in training exercises in the Gulf of Naples; these were held during the visit of German Field Marshal Werner von Blomberg.

Another major fleet review took place on 5 May 1938, this time to honor German dictator Adolf Hitler during his state visit.

[3] Upon Italy's entrance into the Second World War on 10 June 1940, Bolzano was assigned to the 2nd Division in the 2nd Squadron, along with the two Trento-class cruisers.

[4] On 9 July, the ship took part in the Battle of Calabria; there, she led the line of Italian heavy cruisers as they engaged their British counterparts.

She was hit by a salvo of three 6-inch (152 mm) shells at 16:05 that killed two crewmen and jammed her rudder to port, forcing her to turn in a tight circle.

[6] After the two fleets disengaged, Italian aircraft misidentified the ship as a British vessel and attacked her, though they failed to score any hits.

[8] In the ensuing Battle of Cape Spartivento, Bolzano engaged the battlecruiser HMS Renown, but neither ship scored any hits before both sides broke off the action.

Bolzano thereafter took part in escort duties for convoys to Tripoli for the next several months to support the Axis forces fighting the North African Campaign.

By August, the surviving Italian heavy cruisers, Bolzano, Trieste, and Gorizia had been reorganized as the 3rd Division.

On 11 August, the three cruisers sortied to intercept a British convoy, but were eventually ordered back after the Luftwaffe denied air support.

Bolzano was formally stricken from the naval register on 27 February 1947, and in September 1949, salvage workers raised the ship and she was subsequently broken up for scrap.