Some 1.4 million years ago, a meteorite 400 feet in diameter slammed into the Earth’s crust at 55,800 miles per hour, releasing energy equivalent to 8,500 Hiroshima bombs. This explosion gouged out the Cratere du Nouveau-Quebec, which is 2.1 miles in circumference.

The crater brims with water of a rare purity: colourless, tasteless, and virtually devoid of mineral content. This rarefied reservoir is fed exclusively by rainwater and snow, and it lacks any natural outlet. The crater’s lake would take some 330 years to renew itself, making the water extremely vulnerable to pollution.