Geyser Hill is a group of thermal features, including geysers, springs, and pools next to Old Faithful Geyser in ...

For more information on the Upper Geyser Basin, visit Yellowstone National Park's website. Formed over thousands of years of erosion caused by hydrothermal activity, water and other natural forces ...

Editor’s Note: This story accompanies the May 2016 issue of National Geographic magazine, devoted entirely to America’s first national park ... Mortar geysers in Yellowstone's Upper Geyser ...

If you buy through a BGR link, we may earn an affiliate commission, helping support our expert product labs. If you’re headed to Yellowstone National Park in Wyoming, there’s a good chance ...