Frank Lloyd Wright’s most iconic home dangles over a Pennsylvania waterfall.

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

America's oldest archaeological site or a muddled case of wishful thinking.

Famously misunderstood wonder of the ancient world

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The world's longest known cave system.

See massive fossils that are over 200 million years old in northeastern Arizona.

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

A museum dedicated to the alleged Roswell Incident.

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

Scale replica of China's ancient terracotta tomb warriors and Forbidden City are the side project of an eccentric millionaire.

A sculpture made of 10 Cadillacs as a monument to the “Golden Age” of the American automobile.

Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

This abstract roadside poultry was saved from demolition by outraged drivers and pilots.

A bizarre roadside attraction and the first instance of miniature golf in the world.

World's second largest particle accelerator, where nature reveals its secrets.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

A chessmaster's dream destination.

What was meant to be a temporary exhibit is now a permanent fixture at the St. Louis Zoo filled with beautiful birds.