LNER Class A4
The Class A4 is a class of streamlined 4-6-2 steam locomotive designed by Nigel Gresley for the London and North Eastern Railway in 1935. Their streamlined design gave them high-speed capability as well as making them instantly recognisable, and one of the class, 4468 "Mallard", holds the world record as the fastest steam locomotive. Thirty-five of the class were built to haul express passenger trains on the East Coast Main Line route from London Kings Cross via York to Newcastle, and later via Newcastle to Edinburgh, Scotland. They remained in service on the East Coast Main Line until the early 1960s when they were replaced by Deltic diesel locomotives. Several A4s saw out their remaining days until 1966 in Scotland, particularly on the Aberdeen - Glasgow express trains, for which they were used to improve the timing from 3.5 to 3 hours.
Santa Fe class 3460
In December 1937, locomotive #3461 set a world record for the longest single run by a steam locomotive by completing the from Los Angeles, California to Chicago without maintenance other than five refuelling stops en route, hauling Train #8, the Fast Mail Express. An average speed of was obtained, including stops; maximum speed during the run was . During steeply graded portions of the run it was, of course, assisted by helper locomotives. Such long distance runs were a goal of railway operating departments, enabling a reduction in locomotive numbers and through increased locomotive utilization, reduce overall costs.