The Moorgate tube crash occurred on the London Underground Northern Line (Highbury Branch) on 28 February 1975 at 08:46 when a southbound train failed to stop at the Moorgate terminus and crashed into the wall at end of the tunnel. Forty-three people died and 74 people were injured, the greatest loss of life during peacetime in the London Underground.
With no fault being found with the train equipment, the Department of the Environment report found that the driver had failed to slow the train and stop at the station and there was insufficient evidence to determine the cause.
The southern end of the Highbury Branch platforms were rebuilt extensively and an automatic system for stopping trains was introduced into dead-ends on the London Underground, regardless of whether the driver brakes the train. This system came to be known informally as Moorgate protection.
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