This 40-room dwelling tucked within a cliff was built by the basin's prehistoric residents.

One of the world's largest telescopes, stares into the night sky with two huge mirrors.

Walk through the actual strap iron cells and solitary chambers of Arizona Territory’s first prison.

An artificial crater field that trained astronauts for lunar exploration.

This Route 66 classic sports a giant fiberglass rabbit that you can ride.

This golf ball–shaped former desert real estate office now houses a UFO museum.

Open since 1938, this diner has kept its fountain, malt machine, and all the gum that greasers left beneath its counter.

Some of the tallest ancient American ruins continue to inspire awe and curiosity.

What is the Thing?

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

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

Ancient pueblos built into the base of a natural canyon wall.

On the outskirts of a reborn ghost town, a decaying post office remembers the bad old days.

America's only nuclear missile silo open to the public.

This historic national park is covered in the stunning ruins of red rock pueblos.

Ancestral Puebloan ruins, natural arches, and box canyons abound in this seldom-visited corner of Monument Valley Navajo Tribal Park.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

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

Dramatic river bend surrounds a natural red-rocked pedestal.