Castelfidardo was the third of four Regina Maria Pia-class ironclad warships built in French shipyards for the Italian Regia Marina in the 1860s. Castelfidardo was laid down in July 1862, was launched in August 1863, and was completed in May 1864. She and her three sister ships were broadside ironclads, mounting a battery of four 203 mm (8 in) and twenty-two 164 mm (6.5 in) guns on the broadside.

The Regina Maria Pia class was a group of four ironclad warships built for the Italian Regia Marina in the 1860s. The class comprised four ships, Regina Maria Pia, San Martino, Castelfidardo, and Ancona. They were built by French shipyards, since Italian yards were unable to meet the demand of the rapidly expanding Italian fleet. The ships were broadside ironclads and mounted a battery of twenty-six muzzle loading guns.