Published on Jan 12, 2014Yellowstone National Park lies on top of a magma chamber that is 35-miles wide, waiting to erupt.The Yellowstone Caldera is the volcanic caldera and supervolcano located in Yellowstone National Park in the United States, sometimes referred to as the Yellowstone Supervolcano. The caldera is located in the northwest corner of Wyoming, in which the vast majority of the park is contained. The major features of the caldera measure about 34 by 45 miles 55 by 72 km. The caldera formed during the last of three supereruptions over the past 2.1 million years. First came the Huckleberry Ridge eruption 2.1 million years ago, which created the Island Park Caldera and the Huckleberry Ridge Tuff. Next came the Mesa Falls eruption 1.3 million years ago, which created the Henrys Fork Caldera and the Mesa Falls Tuff. Finally came the Lava Creek eruption 640,000 years ago, which created the Yellowstone Caldera and the Lava Creek Tuff.