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 Henry’s 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.