The Great Train Robbery of 1963 was the most famous raid of an era in which some criminals became celebrities.
The gang, taking inspiration from the rail robberies of the Wild West, raided a Glasgow to London mail train and escaped with £2.6m in used bank notes - a record haul at that time.
The mastermind was Bruce Reynolds, a known armed burglar.
Using inside information on mail movements, he assembled a gang to intercept the overnight train in a quiet part of Buckinghamshire.
The robbers struck on 8 August 1963 when the train stopped near Cheddington after the gang had changed a signal to red.
Fifteen men wearing ski masks and helmets swarmed onto the train and grabbed 120 bags of money.
Train driver Jack Mills was struck over the head with an iron bar, although it has never been established who was responsible, and he would never work again.
Police launched an immediate manhunt for the robbers, whose crime had captivated the British public, because of its scale.
Five days after the robbery, a tip-off led police to the gang's hideout at Leatherslade Farm, about 20 miles from the crime scene, near Oakley.
The gang had escaped there to share out the proceeds of their robbery, which would amount to more than £40m in 2009.
It is believed the men played Monopoly at the farmhouse using some of the notes stolen from the mail train.
They fled the property before police arrived, but their fingerprints were found all over the house.
The gang contained a number of members who already had criminal records, which provided vital evidence for police.
Nine days after the robbery, Charlie Wilson became the first member of the gang to be arrested and charged.
By January 1964, police had gathered enough evidence for 12 of the 15 to be put on trial in Aylesbury, Buckinghamshire.
By April all 12 men had been convicted, with only one of them, Roger Cordrey, who gave back his £80,000 share of the money, pleading guilty.
Eleven of the men were each sentenced to between 20 and 30 years in prison.
In passing sentence, Mr Justice Edmund Davies focused on the violence used against Mr Mills.
He said: "Let us clear out of the way any romantic notions of daredevilry. This is nothing less than a sordid crime of violence inspired by vast greed."
The 12th convicted man, solicitor John Wheater, was jailed for three years for obtaining the farm as a hideout.
However, it was accepted he had not known about the robbery until after it had happened.
The three Great Train Robbers not put on trial in 1964 had all been jailed within five years.
They included Buster Edwards, later the subject of a film starring Phil Collins, who went on the run to Mexico but gave himself up in 1968, and mastermind Reynolds.
Within two years of the first trial, both Charlie Wilson and Ronnie Biggs had escaped from prison, adding to the notoriety surrounding the robbery.
Wilson was caught in Canada in 1968, but Biggs became the UK's most famous fugitive as he continued to evade recapture until giving himself up by flying back to the UK from Brazil in 2001.
He was immediately arrested and taken to high-security Belmarsh prison to serve out the remainder of his original sentence, before later moving to Norwich prison on compassionate grounds in 2007.
His lawyers say he has suffered two strokes and now cannot speak or eat due to facial paralysis.
His son Michael, whose birth had prevented Biggs's extradition from Brazil, has campaigned for his father's release ever since his return to the UK.