The Midway Geyser Basin's Grand Prismatic Spring is the largest hot spring in Yellowstone and one of the largest hot springs in the world. Measuring approximately 370 feet in size and around 121 ...

How the Grand Prismatic Spring Gets Its Kaleidoscopic Colors The beating heart of Yellowstone National Park is without a doubt the Grand Prismatic Spring—the largest hot spring in the U.S.

Things are getting hotter than a Dutton family feud. Yellowstone National Park, known for erupting geysers like Old Faithful, is home to one of earth’s largest volcanic systems, with the ...

Editor’s Note: This story accompanies the May 2016 issue of National Geographic magazine, devoted entirely to America’s first national park. Find more at natgeo ...