The Breitspurbahn was a planned 3,000 mm (9 ft 10 1⁄8 in) broad-gauge railway, proposed by Adolf Hitler during the Nazi regime in Germany, supposed to run with double-deck coaches between major cities of Grossdeutschland, Hitler's expanded Germany and neighbouring states.
41 different locomotive designs were suggested by the industry partners. These ranged from classical steam locomotives through steam turbine, gas turbine-electric and diesel-hydraulic to electric locomotives. The designs ranged from 12 axles (UIC: 3'Fo3', Whyte: 6-12-6) to 52 axles (UIC: 2'Fo'Fo'2' + 5T5 + 5T5 + 2'Fo'Fo'2', Whyte: 4-12-12-4 + 10-10 + 10-10 + 4-12-12-4). Power ranged from 11,400 to 18,400 kW (15,300 to 24,700 hp). All locomotives would have automatic couplers, ranged from Janney couplers to SA3 couplers. Several designs were short listed with passenger locomotives to be mainly electric and diesel-hydraulic with SA3 couplers, and freight locomotives to be mainly conventional steam with Janney couplers.