This bird-shaped rock formation defies gravity, time, and classification.

Some 2,000 carvings show this rare desert spring has been an oasis for travelers for over a thousand years.

This isolated outpost was once the only place to cross the Colorado River for hundreds of miles.

When it was built in 1929, this historic bridge was the only place to cross the Colorado River for 600 miles.

The unusual patterns in this rock formation result from two distinct modes of weathering.

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 tunnel with windows, so you don't miss out on the impressive views.

Inside this casino, visitors are treated to slot machines and a rare German Christmas pyramid.

The largest source of fossilized insects anywhere.

When ecosystems collide in the arid Southwest.

The site of the gruesome massacre—and maybe cannibalism—of five men, a tragedy that made Alferd Packer infamous.

A dangerous narrow-gauge railroad once traced a route through this striking canyon.

The fifth-longest natural arch in the world, and the longest outside China.

At this gas station in the middle of the desert, a convenience store has been carved directly into the rock.

Inside this striking glass building, visitors can see thousands of dinosaur fossils in the positions that nature deposited them more than 150 million years ago.

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

A beautiful geyser under environmental threat.

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

10,000 flowered plants bloom in the City of Roses.

The longest continuous lava tube in Oregon.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

Despite time, colonization, and the brutal New Mexican heat, these Pueblo ruins still stand.

This southwest-styled home in Santa Fe claims to be the oldest house in America thanks to an ancient bit of foundation.