Last London "Pea Souper"

When smoke from coal-burning fires mixes with fog, the result is a blinding, choking blanket of smog, known in London as a "pea souper". In December 1952, during the city's last pea souper, 3,500-4,000 people died from acute bronchitis. Visibility in the street was down to 30 cm (12 in) and cinemas closed because it was impossible to see the screens.