A cave's rare beauty held a cavernous secret hidden underground.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

A burnt-out motel with priceless Native American artwork in the basement, redeveloped into apartments.

Thousands of pieces of art have been carved into the rock at the site of an ancient volcanic eruption.

This rooftop sign has been confusing Milwaukee-bound airline passengers for decades.

A bizarre house filled with an astounding array of collections.

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.

A self-built castle made by a mysterious man.

The hallowed remains of a 900-year old Ancestral Pueblo great house.

An old railroad grade built for the construction of Hoover Dam is now a recreational trail featuring several tunnels and sweeping views of Lake Mead.

Formerly the world's largest, this Willy Wonka-esque contraption runs 24/7.

A land of debatable treasure.

A homage to the King at the hotel where he revived his career.

Temporary Burning Man sculpture made of two 18-wheelers.

Three hundred years of preserved Spanish colonial history in San Antonio.

The summer home of the largest colony of bats in the world.

Continuing the tradition of the dime museum in style.

This stone, said to have once been a young woman, is sacred to the Dakota and Lakota nations.

This Old West eatery along America's Loneliest Road was originally a stop on the Pony Express.

US-50 in Nevada is known as "the Loneliest Road in America," but this earlier iteration of the route is even lonelier.

Now a city park, this site started as a stage stop, then was a working ranch, and finally became a dude ranch that specialized in letting wannabe divorcees establish Nevada residency.

This former open-pit manganese mine is now a massive graffiti canvas.

In the middle of the desert, miles from any human life, sat an anomalous pay phone that still magically answers your calls.

A macabre tour of Hollywood’s deadly history.