Chelsea is an affluent area in west London, England, due south-west of Charing Cross by approximately 2.5 miles. It lies on the north bank of the River Thames and for postal purposes is part of the south-western postal area. Chelsea historically formed a manor and parish in the Ossulstone hundred of Middlesex, which became the Metropolitan Borough of Chelsea in 1900. It merged with the Metropolitan Borough of Kensington, forming the Royal Borough of Kensington and Chelsea upon the creation of Greater London in 1965.