Zara was a heavy cruiser built for the Italian Regia Marina, the lead ship of the Zara class. Named after the Italian city of Zara, the ship was built at the Odero-Terni-Orlando shipyard beginning with her keel laying in July 1928, launching in April 1930, and commissioning in October 1931. Armed with a main battery of eight 8-inch (200 mm) guns, she was nominally within the 10,000-long-ton (10,000 t) limit imposed by the Washington Naval Treaty, though in reality she significantly exceeded this figure.
Italian cruiser Zara
Profile and plan drawing of the Zara class
Zara (second from right) along with Fiume and Pola in Naples
Zara on gunnery exercises in 1938
A heavy cruiser was a type of cruiser, a naval warship designed for long range and high speed, armed generally with naval guns of roughly 203 mm (8 inches) in calibre, whose design parameters were dictated by the Washington Naval Treaty of 1922 and the London Naval Treaty of 1930. Heavy cruisers were generally larger, more heavily-armed and more heavily-armoured than light cruisers while being smaller, faster, and more lightly-armed and armoured than battlecruisers and battleships. Heavy cruisers were assigned a variety of roles ranging from commerce raiding to serving as 'cruiser-killers,' i.e. hunting and destroying similarly-sized ships
HMS Frobisher, a Hawkins-class cruiser around which the Washington Naval Treaty limits for heavy cruisers were written.
Armoured cruiser USS Tennessee, armed with four 10-inch (250 mm) guns, ca. 1907
HMS Hawkins, lead ship of her class.
HMAS Canberra, a County-class "treaty cruiser".