The site where a nuclear bomb was lowered over 8,000 feet underground and detonated as an experiment in natural gas extraction.

In the middle of a suburban Denver neighborhood is a cave that once provided solace for a prominent Ute chief and his family.

This unusual lava tube spouts seawater during high surf.

Mining town from the late 1890s, once home to Calamity Jane.

Despite his legacy of work in Spain, Cuba, and Florida, the larger-than-life writer's grave is a simple affair tucked in an Idaho cemetery.

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

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

The NASA scientists behind Apollo 11 started out developing Nazi weapons at this abandoned German rocket factory.

These ancient sacred grounds granted amnesty to those who managed to reach them.

A controversial memorial at the place where Captain Cook met his violent end.

The largest man-made crater in the U.S. marks the spot where we once tested mining with nukes.

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

This attraction was abandoned after the Chernobyl disaster.

A picture-perfect town, perfect for blowing up.

A small museum filled with over 1,000 clocks, and one particular clock calibrated to run until the year 9999.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

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

Famously misunderstood wonder of the ancient world

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

Hidden beneath the streets of London is a secret subway that only carried mail.

A seemingly endless landscape of pure salt stretches far across Bolivia.

The world's highest and most dangerous infinity pool lies at the precipice of Victoria Falls.

Dramatic river bend surrounds a natural red-rocked pedestal.