On 8 August 1963, a gang of thieves held up a British Royal Mail train on its journey from Glasgow to London.
They stole more than £2 million.
It was the biggest ever raid on a British train.
Most of the robbers ended up behind bars, but most of the money has never been recovered.
The robbery still occupies a unique place in the history of British crime.
In 2012 Chloe Hadjimatheou spoke to Reginald Abbiss who was a young BBC journalist who covered the story.
(Photo: The train involved in the robbery. Credit: Getty Images)