Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

This sinkhole in the Arizona desert is filled with carbonated, arsenic-rich water

The drama of nature in full effect in this Nevada State Park.

These markers are used to document elevation changes around the famed dam.

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

This once-booming Gold Rush town is now home to a herd of feral donkeys.

A century-old miner's quarters turned mansion.

A tribute to the statues of Easter Island along Route 66.

Don't blink or you'll miss it.

The remains of a boarding school designed to forcibly assimilate Native American children.

One of the largest, oldest, darkest, quietest motel rooms in the world.

In a 345-million-year-old cave that's 200 feet underground, dinner awaits.

A classic Route 66 landmark that was built with scrap lumber and is held together with kitsch and puns.

This Native American settlement dates back to the Pueblo II period.

Colorful sand dunes create a unique attraction in this part of Utah's red-rock country.

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

This mesmerizing and surreal landscape features intricate patterns of white and red sandstone.

Most-visited and most-photographed slot canyon in the American Southwest.

A sharp bend in a dramatic river canyon cut through red rocks.

Archaeologists believe this panel of petroglyphs depicting descending sheep and other figures in Glen Canyon are 3,000 to 6,000 years old.

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.

A mapping error in the 19th century made loggers think this section of the forest was underwater.

Where you can photograph wild black bears without worrying about becoming dinner.