On 10 December 1868 the world’s first traffic lights appeared outside the Houses of Parliament in London to control traffic flow around the new Parliament Square.
The lights were designed by J P Knight, a railway signalling engineer. They used semaphore arms to direct the traffic during the day, and red and green gas lamps at night, all operated by a police constable.
Unfortunately, despite their success at directing traffic, the first lights didn’t last all that long. A leak in the gas line caused them to explode, in so doing reportedly killing the police operator. It would be another thirty years before traffic lights really took off, this time in America where semaphore lights sprung up in various designs across the different states.
It wasn’t until 1914 that the first electric traffic light was developed, in Salt Lake City by policeman Lester Wire. In 1918 the first three-colour lights appeared in New York City. They arrived in London in 1925, located at the junction of St James’s Street and Piccadilly Circus. But these lights were still operated by a policeman using a series of switches. Wolverhampton was the first place in Britain to acquire automated lights, in Princess Square in 1926.