Yellowstone National Park spans an area of 3,468.4 square miles (8,983 km2),[1] comprising lakes, canyons, rivers and mountain ranges. Yellowstone Lake is one of the largest high- altitude lakes in North America and is centered over the Yellowstone Caldera, the largest supervolcano on the continent. The caldera is considered an active volcano. It has erupted with tremendous force several times in the last two million years. Half of the world's geothermal features are in Yellowstone, fueled by this ongoing volcanism.
