Mainline steam trains in Great Britain
The most famous steam locomotive operating on the British main line is the 1923 built "Flying Scotsman". After being taken into public ownership in 2004, following a decade long refit it returned to mainline service in 2016. The fastest steam locomotive ever built, the 1938 built "Mallard", was also certified for main line operation briefly in the 1980s.
Norfolk and Western 1218
During 1218's excursion career, it was the most powerful operational steam locomotive in the world, with a tractive effort of , well above the next-strongest-pulling operational steam locomotive (Union Pacific 3985, with a tractive effort of ). However, when Union Pacific 4014 finishes its restoration, 1218 will become the locomotive with the second highest tractive effort. Unlike diesel-electric locomotives of similar high tractive effort (for starting heavy trains) but typical for a steam locomotive, it could easily run at 70 miles per hour (113 km/h) and more.