Timeline: The Great Train Robbery in pictures
The Great Train robbery was an enormous operation involving a gang of at least 15 men, mostly from South London, headed up by notorious criminal Ronnie Biggs and mastermind Bruce Reynolds.
Reynolds' plan was to hold up the Glasgow to Euston night mail train as it passed through the Buckinghamshire countryside.
The train appeared shortly after 3am and stopped at a set of fake signals the gang had put up. Driver Jack Mills, who got out to see what was going on, was hit over the head. He was treated for three days in hospital.
However, the gang had stopped the train near a sheer drop so found it impossible to unload the cash. Even worse, it quickly became apparent that the driver they had brought along couldn't work the controls. The men realised they needed Mills after all, so he was forced back into the carriage to move the train along.
The train was finally stopped a mile and a half down the track where the gang unloaded £2.6 million, worth around £46 million today.
The gang fled to a house at Leatherslade Farm in Oakley. In front of the farmhouse was a half-dug hole, believed to have been intended to bury the money.
But after a joint investigation in Buckinghamshire and London, most of the men had been arrested by December that year.
File photo dated 19/08/1963 of a police-car escorting the lorry and two Land Rovers, which police believe the bandits carried much or all of their haul after the 2.6 million pound mail train robbery, out of Leatherslade Farm, Oakley, Bukinghamshire, where the gang hid after the crime.
Despite this, two of the gang - Charlie Wilson and Ronnie Biggs - soon escaped prison. Biggs broke out of Wandsworth prison only 15 months into his 30 year sentence, and spent more than three decades on the run before he finally returned to face arrest in 2001.