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.
Steam locomotive
The most-manufactured single class of steam locomotive in the world is the 0-10-0 Russian locomotive class E steam locomotive with around 11,000 produced both in Russia and other countries such as Czechoslovakia, Germany, Sweden, Hungary and Poland. The Russian locomotive class O numbered 9,129 locomotives, built between 1890 and 1928. Around 7,000 units were produced of the German DRB Class 52 2-10-0 Kriegslok.
The British GWR 5700 class numbered about 863 units. The DX class of the London and North Western Railway numbered 943 units, including 86 engines built for the Lancashire and Yorkshire Railway.