The Cheltenham Flyer was a name given to the Cheltenham Spa Express service that operated between Cheltenham and Paddington which, for many years, was the fastest start-to-stop run in Britain and the world. The name was dreamt up by the press, it quickly captured the imagination of the public and was subsequently unofficially adopted by the GWR.
 
The Express' first record came in June 1923 when the timing for the Swindon to Paddington section of the run was recorded as 75 minutes, averaging a speed of 61.8 miles per hour. In July 1929 it achieved an average speed of 66.2 mph and it was at this point that the Cheltenham Flyer became the world's fastest train.
 
This threw the challenge out to other railway companies and in April 1931 the Canadian Pacific Railway stole the title of the world's fastest train, with one of its trains recording an average speed of 68.9 mph.
 
However, the GWR did not take loosing this title lightly and strove to regain the record. In July 1931 the Cheltenham Flyer struck back and regained the title during the Swindon to Paddington run, achieving an average speed of 69.2 mph. The GWR was not a company to sit on its laurels however, and on 6 Jun 1932 the Cheltenham Flyer, hauled by Tregenna Castle, smashed its own speed record, this time reaching an average speed of 81.6 mph.
 
In September of that same year the GWR reduced the publicized timings for the Cheltenham Flyer service from 70 to 65 minutes, scheduling the train to run at an average speed of 71.3 mph. This was the first time in 100 years of railway history that a train service had been officially scheduled to run at over 70 mph.
 
Within three years the world speed title had gone overseas once again. The Cheltenham Flyer never regained the record but had nevertheless already secured its place in railway history.