In Pictures: The Great Smog of 1952
Choked streets

For years London was synonymous with thick fogs - indeed, the city's pea-soupers were immortalised in the works of Charles Dickens. But the smoke-laden fog that shrouded London from 5-9 December 1952 was the worst single incident of air pollution in the UK.

Conductors walked in front of buses holding torches or flares in order to see street signs - and so drivers could see them.

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