In early June 1912, residents of southeast Alaska began to feel earthquakes daily. Earthquakes are common in this region, which is well-known for its geologic instability, though these were getting stronger. The remaining two families at Katmai village evacuated, and they were just in time. On June 6th, the largest volcanic eruption of the twentieth century exploded. The skies darkened and the sun disappeared for more than 60 hours, and the aftermath of the explosion was felt hundreds of miles away.

This week on America’s National Parks: the Novarupta volcano in Katmai National Park.