Catterick Bridge station sat on the Eryholme to Richmond branch of the London and North Eastern Railway, connecting Richmond to the East Coast Main Line. By 1944 it was the freight gateway for the vast Catterick army camp - a sprawling training and logistics base that had ballooned during two world wars into the largest military complex in northern England. The goods yard handled everything the army needed: rations, fuel, kit, vehicles, and steadily increasing amounts of ammunition as the D-Day buildup accelerated. On the day of the disaster, soldiers were loading rail wagons with explosives destined for the invasion stockpiles being assembled along the south coast. One witness later told the local newspaper that he had watched the same loading crew days earlier handling ammunition carefully, two men to a box. On 4 February, he said, they were practically throwing them into the wagons.

A large explosion ripped through the goods yard at about 3:55 pm. The four privates loading the wagons were directly at the epicentre of the blast. Three were from the Royal Pioneer Corps; the fourth from the Royal Army Ordnance Corps. Their remains were not initially recovered. Three days afterward the Northern Despatch was still listing them as missing. What survived of them was eventually buried in four graves in the churchyard of St Mary's at Hornby, five miles to the south-west. The other dead included the stationmaster of Catterick Bridge, two female clerks from the goods office, a Royal Air Force serviceman, one other military casualty, and several civilians. Two of the dead were never identified. The Military Court of Inquiry that convened afterwards apportioned no blame and recorded all twelve deaths as accidental. A theory that a primed grenade had been mixed into the consignment was raised and not resolved.

A lorry driver in a hut more than thirty feet from the blast was thrown off his feet and badly wounded. Despite his own injuries he joined the rescue parties, working through the wreckage knowing perfectly well that unexploded ordnance was scattered everywhere. For this he was awarded the Edward Medal by King George VI, gazetted in June 1944. The medal is now in the keeping of Richmond Council. Another improvised act of courage stopped a worse disaster: a taxi driver ran up the line carrying a makeshift flag, flagging down an incoming train before it could pile into the wreckage on the damaged track. The trains were frequent on Friday afternoons, the station was crowded, and a second collision could have multiplied the casualties many times over. He is not named in the surviving accounts. The railway hotel was destroyed in the blast. Local legend insists that the cellars were raided for the beer that survived, and that the hotel's licence to sell alcohol continued formally in force until 1984 because nobody could be bothered to have it cancelled.

The British Army's own report into the explosion was conducted but its findings were not released to the public inquiry or to the press, on wartime grounds. An inquest was held the following day on the eight identified casualties. Beyond that, the disaster was effectively buried beneath the censorship covering all military matters in the months before D-Day. Newspapers in the spring of 1944 had little space and even less freedom for stories about ammunition handling errors at a North Yorkshire siding. The dead were locally mourned and locally remembered. Some of their names appear on the war memorial at Brompton-on-Swale, near to where the station stood. The branch line itself closed to passengers in 1969 under the Beeching cuts. Today there is almost nothing left of Catterick Bridge station, and almost no public memory of what happened in its goods yard on a Friday afternoon four months before the Normandy landings.