The Flying Scotsman is an express passenger train service that operates between Edinburgh and London, the capitals respectively of Scotland and England, via the East Coast Main Line.

The first Special Scotch Express ran in 1862, with simultaneous departures at 10:00 from the GNR's London King's Cross and the NBR's Edinburgh Waverley.

As a consequence of this, all three members of the East Coast Joint Stock became part of the newly formed London and North Eastern Railway (LNER).

In 1924, the LNER officially renamed the 10:00 Special Scotch Express linking Edinburgh and London in both directions as Flying Scotsman, its unofficial name since the 1870s.

To further publicise the train, a recently built A1 Class locomotive – at first numbered 1472 and, subsequently, 4472 – was named after the service and put on display at the 1924 British Empire Exhibition.

Ten locomotives of Classes A1 and A3, which were to be used on the service, were provided with corridor tenders; these avoided engine crew fatigue by enabling a replacement driver and fireman to take over halfway without stopping the train.

A driver and fireman were able to access the locomotive from the train through a narrow passageway inside the tender tank plus a flexible bellows connection linking it with the leading coach.

[6][7] Use of the corridor tender for changing crews on the move in an A4 locomotive is shown in the 1953 British Transport Films' Elizabethan Express, the name of another London-to-Edinburgh non-stop train.

In the late 1950s British Railways (BR) was committed to dieselisation, and began devising a replacement for the Gresley Pacifics on the East Coast Main Line.

[19] As a major link between the capital cities of England and Scotland, the Flying Scotsman was an extremely long and heavy train, especially in the days before road and air transport became common.