It's half a century since one of London's worst rail tragedies.
On 28 February 1975, a London Underground train sped into Moorgate station during the height of the morning rush hour. It did not stop at the platform, but carried on without slowing. Moments later, it rammed into the barriers at the end of the line. 43 people died and 74 were injured.
It is the worst peace-time accident in London Underground's history, and was London's worst disaster of any kind in the 1970s.
The tragedy took place on the Northern City line, which runs out of Moorgate up towards Highbury and Finsbury Park. The line is today operated by Great Northern but was part of London Underground at the time, badged as a branch of the Northern line.
The crash took place at 8.46am. Witnesses described the train hurtling into the station, though the driver appeared to be calm and alert. The train then entered the over-run tunnel for two carriage lengths before ploughing through barriers and sand heaps into the wall.
The first coach was bent in two, with the front and rear lifting to the tunnel roof. The second coach ploughed underneath it. The driver was killed instantly, his cab compressed to just 15 cm.
The first rescuers found a scene of horror. "It was like being in a mine shaft after an explosion," said PC Graham Bridger.
"Many of the victims were writhing in agony and were screaming for individual attention," said one medic. "It was obvious from an early stage that the main problem was the disentanglement of a heap of people, many of whom appeared to be in imminent danger of suffocation."
Rescuers were presented with many other challenges: high temperatures, cramped conditions, difficulties in radio communication, a lack of fresh oxygen in the confined space, and a cloud of black grime dislodged from the tunnel walls. Survivors came out "looking literally as though they had been pulled through a sack of soot," according to Bridger.
Firefighter Brian Goodfellow painted an equally grim picture: "I managed to pull out at least 16 badly injured commuters, but there are some poor devils down there we can't do much for. Their bodies had been forced down in among the wheels".
It took many hours to reach everybody. The last person to be rescued alive was 19-year old police trainee Margaret Liles. She endured 13 hours trapped in the wreckage of the front carriage and had to have her foot amputated at the scene in order to be freed. "My leg was completely numb," she later told the press, "I only thought it was broken. They told me they were going to put me to sleep to help get me out, which was common sense. I didn't know anything about it until I got back from surgery."
How did the crash happen?
To this day, the circumstances around the crash remain clouded. No mechanical issue was discovered with the train, signals or track. The official enquiry could point only to the driver Leslie Newson. Yet there was insufficient evidence to decide whether this experienced driver had crashed the train through inattention, deliberate act or some kind of sudden physical affliction. The post-mortem found elevated levels of alcohol in Newson's blood, but this might have been down to decompositional processes after death.
Legacy and memorials
Important changes were made to train operation in the wake of the Moorgate crash. Most importantly, an automatic-stop system was installed at all termini. This triggers emergency brakes if a train approaches the end of a tunnel at more than 12.5 mph. Officially known as TETS (for Trains Entering Terminal Stations), the failsafe is commonly called the Moorgate Protection.
The disaster is remembered with two memorials in the area. In Finsbury Square, a plain marble slab records the names of all those who died, along with a tribute to the emergency services who saved many more. The memorial was unveiled in 2013, almost 40 years after the disaster. A second plaque was placed on the wall of Moorgate station a year later.
