Many were taken aback by the geographic details of the canyon, including its many colors and rock formations ... Grand Canyon of the Yellowstone is included in the park's seven-day admission ...

CHEYENNE, Wyo. (AP) — A surprise eruption in Yellowstone National Park shot steam, water and dark-colored rock and dirt high into the sky Tuesday and sent sightseers running for safety.

It really feels more like four or five parks with vastly different landscapes including forested mountains, bubbling mudpots and steamy fumeroles, the largest high elevation lake on the continent, and ...