Milwaukee Road class F7
The F7s are major contenders for the fastest steam locomotives ever built, as they ran at over daily. One run in January 1941 recorded by a reporter for "Trains" magazine saw achieved twice—in the midst of a heavy snowstorm. Baron Gérard Vuillet, a French railroading expert, once recorded a run between Chicago and Milwaukee where the locomotive reached and sustained an average for . However, the British locomotive LNER Class A4 4468 "Mallard" is officially accepted to be the world's fastest, with a run recorded at but authenticated at 126 mph in 1938.
Locomotives of the London and North Eastern Railway
The London and North Eastern Railway (LNER) produced several classes of locomotive, mostly to the designs of Nigel Gresley, characterised by a three-cylinder layout with a parallel boiler and round-topped firebox. It produced the most iconic locomotive of its day, 4468 'Mallard', the holder of the world steam locomotive speed record. It also built the world-famous 4472 'Flying Scotsman'. However, its locomotive inheritance was much greater than just the 'A4 Class', it also produced highly successful mixed-traffic and freight designs.Including the Manchester, Sheffield and Lincolnshire Railway