The Classis Britannica (literally, British fleet, in the sense of 'the fleet in British waters' or 'the fleet of the province of Britannia', rather than 'the fleet of the state of Britain') was a provincial naval fleet of the navy of ancient Rome. Its purpose was to control the English Channel and the waters around the Roman province of Britannia. Unlike modern (and some contemporary Roman) "fighting navies", its job was largely the logistical movement of personnel and support, and keeping open communication routes across the Channel.
There is no literary reference in the classical historians to the Classis Britannica by that name, and archaeological evidence is also tantalizingly scant (although tiles stamped CLBR are common along the east Kent coast and in London, suggesting either government buildings or an early instance of army surplus), meaning that details of its history and form are unfortunately based on a large degree of interpretation.
Other articles related to "classis britannica, classis":
... occupied by the fleet's marines at Dover, suggesting this was in fact a major base of the Classis ...