Rochester-upon-Medway was a local government district in north Kent, England from 1974 to 1998. The district was formed as the District of Medway under the Local Government Act 1972 on 1 April 1974, as a merger of the municipal borough and city of Rochester, the borough of Chatham and most of Strood Rural District. The district council was granted a charter entitling it to be known as the Borough of Medway, and preserving the mayoralties of Rochester and Chatham.