Times Up! The Caldera at Yellowstone is Sending Warnings - America Is Out of Time! a.k.a. the Yellowstone Supervolcano, is the caldera located in Yellowstone NP in the NW corner of Wyoming. The major features of the caldera measure about 34 by 45 miles (55 by 72 km). Based on best geological evidence, the Supervolcano erupted 2.1 million, 1.3 million, and 640,000 years ago. Given its size and location, the next eruption of the volcano will have a disastrous impact on the USA and the World!