The Etna class were two cruisers originally ordered in Italy for the Thai Navy in 1938 and subsequently requisitioned for service by the Italian Navy on the outbreak of World War II, neither ship was completed and the damaged hulls were scrapped after the war.

The ships were to displace 5,500 tons and be armed with six 6-inch (152 mm) guns in three twin turrets.

Work on the vessels continued after Italy entered the war at a slowed pace until the Italian government took over the contract in late 1941.

Extra cargo space comprising four holds of 600 cubic metres (21,000 cu ft) total volume, was also included to enable the ships to act as fast transports to North Africa.

Although both vessels were sabotaged before being captured by the Germans, they were able to continue some construction work before abandoning the project.