Yellowstone Caldera, the biggest volcano in USA
Yellowstone Caldera is the volcanic caldera and supervolcano located in Yellowstone National Park in USA.
It was formed during the last of three supereruptions over the past 2.1 million years. The caldera and most of the park are located in the northwest corner of Wyoming.
The major features of the caldera measure about 34 by 45 miles.