The city of Mammoth Lakes sits on the edge of the Long Valley Caldera formed around 700,000 years ago. This caldera is 15 miles in diameter and is North America's second largest.

1. The Long Valley Caldera in which the city of Mammoth Lakes sits was thought until recently to be the largest Caldera in the United States, do you know what caldera took this title?

2. What caldera nearly wiped out the human race?

3. The explosion of which caldera is believed to be the basis for the fabled city of Atlantis?

Answers are below.

1. The Long Valley Caldera in which the city of Mammoth Lakes sits was thought until recently to be the largest Caldera in the United States, do you know what caldera took this title?
It was recently discovered by detailed satellite mapping that Yellowstone National Park sits on the largest caldera in North America. It measures 30 miles wide by 45 miles long. Subsequent research has shown that this caldera erupts approximately every 600,000 years. It is disturbing to realize the last eruption was approximately 600,000 years ago. This was such a devastating event that a thick layer of ash covered most of North America and wiped out the dinosaurs that then inhabited North America at distances of over 1,000 miles!

2. What caldera nearly wiped out the human race?
Lake Toba in Sumatra, Indonesia is believed to be the largest resurgent caldera on earth. The caldera measures 100km long by 30km wide. This gigantic caldera erupted approximately 75,000 years ago, and is estimated to have spewed out 2,800 cubic kilometers of material. This eruption is believed to have caused the worldwide decimation of the human species that occurred at this time, when humans are believed to have dwindled from countless millions to as few as 1,000 individuals.

3. The explosion of which caldera is believed to be the basis for the fabled city of Atlantis?
The Greek Isle of Santorini is a caldera that exploded sending its cities and citizens to the bottom of the Mediterranean, thus it is believed to be the basis for the ancient mystical city of Atlantis. This eruption brought down the mighty Minoan civilization by covering the isle of Crete with ash and wiping out humans, animals, and crops.