Located away from the main boardwalk, the Grand Prismatic Overlook Trail is a 1. ... Access to the Grand Prismatic Spring is included in Yellowstone's seven-day pass ($35) and there are no set ...

Discover Yellowstone National Park, the geological crown jewel of the United States, home to the famous Grand Prismatic ...

A detailed look at Yellowstone's magma storage system finds that only one region is likely to host liquid magma in the long ...

An expert from the Yellowstone Volcano Observatory has revealed some of the most likely impacts of an eruption in the famed ...

This Yellowstone National Park one day itinerary takes you to all the park's highlights including Old Faithful and Grand ...

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.

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 ...