List of cruiser classes of the Royal Navy

This is a list of cruisers of the Royal Navy of the United Kingdom from 1877 (when the category was created by amalgamating the two previous categories of frigate and corvette) until the last cruiser was deleted more than a century later. There are no longer any cruisers in the Royal Navy.

Armoured cruisers were protected by a belt of side armour and an armoured deck. In the Royal Navy this classification was not actually used, the term first class cruiser being used instead for both armoured cruisers and large protected cruisers. Thus, the first class cruisers built between the Orlando class (1886) and the Cressy class (1897) were, strictly speaking, protected cruisers as they lacked an armoured belt. The first class cruiser was succeeded by the Battlecruiser in the Royal Navy.

Protected cruisers were so-called because their vital machinery spaces were protected by an armoured deck and the arrangement of coal bunkers. The ships below are all protected cruisers, but were rated as second and third class cruisers by the Royal Navy. The third class cruiser was not expected to operate with the fleet, was substantially smaller than the second class and lacked the watertight double-bottom of the latter. With the advent of turbine machinery, oil firing and better armour plate the protected cruiser became obsolete and was succeeded by the light cruiser.

The scout cruiser was a smaller, faster, more lightly armed and armoured cruiser than the protected cruiser, intended for fleet scouting duties and acting as a flotilla leader. Essentially there were two distinct groups - the eight vessels all ordered under the 1903 Programme, and the seven later vessels ordered under the 1907-1910 Programmes. The advent of better machinery and larger, faster destroyers and light cruisers effectively made them obsolete.

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