Zara-class cruiser

The Zara class was an Italian heavy cruiser design of the Regia Marina from the early 1930s. Four ships of the class were completed, Zara, Fiume, Pola and Gorizia, all of which saw extensive service during the war.

Design

The Zaras were essentially an improved Trento class tasked with dealing with the latest French designs.

The Trentos had been designed to the limitations of the Washington Naval Treaty, which stated that cruisers had to be 10,000 tons or less, and armed with 8-inch (203 mm) guns or smaller. The weight limitation made it impossible to design a ship with those guns and armour able to stop shells of the same caliber. A typical Washington design had 76 mm (3 in) in its armour belt, and less on other areas of the ship. These thicknesses were reasonably good against destroyer and light cruiser weapons (typically armed with 5–6-inch (127–152 mm) guns), but insufficient against the 120 kg (265 lb) shells that 203 mm (8 in) guns fired, capable of piercing even 150 mm (6 in) of armour at medium range. In general, in order to be effective, armour should be roughly the same thickness as the diameter of the shells fired against it.