On Tuesday 17 October 2000 the 1210 GMT GNER Intercity 225 train from London to Leeds was derailed outside the Hertfordshire town of Hatfield, killing four people. It was the third serious rail disaster in three years after the Southall and Paddington crashes.
The train, which was carrying about 200 passengers, was 17 miles into its journey at 1225 when it hit a broken rail. Four of the nine carriages were derailed and three more were flung over on their side.
Click through BBC News Online's guide to the crash site to find out what happened to the train.