This article was originally published on mentalfloss.com as The Great Smog Descended on London More Than 70 Years Ago—And its Cause Took Almost As Long to Discover.

Still, this is not the full extent of the catastrophe that's etched in history as the Great Smog of London. What was life like then, and did the smog's departure really mean an end to the problem?

In the so-called Great Smog of London of December 1952, about 4,000 more people reportedly died from air pollution than in any year. Will there be a revival of this sort of “dirty fog”?