This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

One of the most remote spots in America and the first protected wilderness area in Nevada, named after an old legend.

New fungal and bacterial species call this deadly lake home.

A whimsical, punny collection of "fence art" outside the tiny mountain town of Baker, Nevada.

This highest peak in Idaho can only be reached by traversing a formation known as "Chicken-Out Ridge."

This crumbling stump is all that remains of what was once thought to be the oldest living organism.

A gothic palace of endless stalagmites and pseudoscorpions waits within one of the world's most beautiful caves.

The longest living non-clonal organisms on Earth.

The oldest badlands in North America, Makoshika State Park takes it name from the Lakota words for broken land.

The United States's largest hand-dug well is topped with a state-of-the-art museum.

These century-old beehive-shaped kilns were built to produce charcoal for nearby mines.

The world's first nuclear power plant is open to visitors looking to role-play a meltdown.

The last physical evidence of the Lewis and Clark trail is one of their autographs etched into this giant rock.

An apocalyptic seismic event creates a deadly chain reaction that ends with a 6-mile long lake developing within weeks.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

A sculpture for the sun and stars, created by Nancy Holt.

A monument to a survivor of harsh pioneer life, frostbite, and primitive surgery.

A rapidly disappearing glacier filled with extinct grasshoppers, perfectly preserved in the ice.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

An architect's childhood fantasy treehouse made real.

A beautiful geyser under environmental threat.