The Great Train Robbery occurred on August 8, 1963, when a group of robbers in the United Kingdom intercepted a Royal Mail train. They used a fake signal to stop the train at a remote location, allowing them to overpower the crew and gain access to the cargo. The robbers made off with £2.6 million, equivalent to about £53 million today. The heist was meticulously planned, involving a team of around 15 criminals. They used various vehicles to transport the stolen money, but their success was short-lived. Most of the robbers were eventually caught, leading to significant prison sentences.