The first traffic signal was installed outside the Houses of Parliament in London in December 1868 — a gas-lit signal with semaphore arms, designed to help pedestrians cross safely amid horse-drawn traffic. It exploded about a month later, injuring its police operator, and it would be several more decades before electric traffic lights became widespread, starting in Cleveland, Ohio, in 1914.
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The first traffic signal was installed outside the Houses of Parliament in London in December 1868 — a gas-lit signal with semaphore arms, designed to help pedestrians cross safely amid horse-drawn traffic. It exploded about a month later, injuring its police operator, and it would be several more decades before electric traffic lights became widespread, starting in Cleveland, Ohio, in 1914.
The year the first traffic signal device was installed to control road traffic.
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Permanent ID limitsregistry.com/limits/LR-FIRST-TRAFFIC-LIGHT
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Limits Registry. LR-FIRST-TRAFFIC-LIGHT. First traffic light. 2026.