Colossus-class battleship (1910)

Colossus at anchor, shortly after completion
Class overview
Name	Colossus-class battleship
Operators	Royal Navy
Preceded by	HMS Neptune
Succeeded by	Orion class
Built	1909–1911
In commission	1911–1921
Completed	2
Scrapped	2
General characteristics (as built)
Type	Dreadnought battleship
Displacement	20,030 long tons (20,350 t) (normal)
Length	545 ft 9 in (166.3 m) (o/a)
Beam	85 feet 2 inches (26.0 m) or 86 feet 8 inches (26.4 m)
Draught	27 ft (8.2 m)
Installed power	25,000 shp (19,000 kW) 18 × water-tube boilers
Propulsion	4 × shafts; 2 × steam turbine sets
Speed	21 knots (39 km/h; 24 mph)
Range	6,680 nmi (12,370 km; 7,690 mi) at 10 knots (19 km/h; 12 mph)
Complement	751–791 (1916)
Armament	5 × twin 12-inch (305 mm) guns 16 × single 4-inch (102 mm) guns 3 × 21-inch (533 mm) torpedo tubes
Armour	Belt: 8–11 in (203–279 mm) Deck: 1.5–4 inches (38–102 mm) Turrets: 11 in (280 mm) Barbettes: 4–11 inches (102–279 mm) Bulkheads: 4 and 8 in (102 and 203 mm) Conning tower: 11 in (280 mm)

The Colossus-class battleships were a pair of dreadnought battleships built for the Royal Navy (RN) at the end of the first decade of the 20th century, the last 12-inch-gunned (305 mm) battleships built for the RN. The sister ships spent their whole careers assigned to the Home and Grand Fleets, often serving as flagships. Aside from participating in the Battle of Jutland in May 1916, and the inconclusive action of 19 August several months later, their service during the First World War generally consisted of routine patrols and training in the North Sea.

The Colossus class were deemed obsolete by the end of the war in 1918 and were reduced to reserve the following year. Hercules was sold for scrap in 1921, although Colossus was briefly used as a training ship. She was hulked in 1923 and sold for scrap five years later.