British Rail Class 74 was an electro-diesel locomotive that operated on the Southern Region of British Railways, rebuilt from redundant Class 71 locomotives in the late 1960s. An electro-diesel locomotive is one that can operate either from an electrical supply, such as overhead catenary or (in this case) an energised third rail, or from an onboard diesel engine. All the locomotives were withdrawn between June 1976 and December 1977; they were scrapped between 1977 and 1981.