The Cornwall Fortress Royal Engineers, was a volunteer unit of Britain's Royal Engineers formed in 1908. It helped to defend the coastal towns of Cornwall and sent engineer units to work on the Western Front. Converted to an air defence role before World War I, it served as a searchlight unit during the Battle of Britain, the Blitz, then, as a light anti-aircraft gun unit, it served in the most heavily attacked part of the South Coast of England throughout 1942–44, including the V-1 flying bomb campaign (Operation Diver).