The contents of this safe survived a 37-kiloton nuclear bomb.

These 40,000-year-old stenciled hands are older than the famous cave art in France and Spain.

A slightly surreal menagerie of structures that were lovingly spared from demolition and reconstructed in a field.

If they push on just the right spot, even the weakest person can move this titanic boulder.

The haunting concrete remains of a Nazi pebble crusher can still be found in this small French commune.

One of the great treasures of Neolithic art lies within this carefully constructed pile of rocks.

A psychedelic labyrinth on the San Francisco bay.

The first declared National Monument in the United States.

Rising from the sea like a stone monster.

Stepping away from the glitz of mobsters and casinos to learn about the other history of Vegas.

Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Hot springs monkey spa in the middle of Hell's Valley.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

Dramatic river bend surrounds a natural red-rocked pedestal.

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

World's largest collection of serial killer artwork and other macabre exhibits.

Rippling sand dunes frozen in the Arizona rock.

These beautiful ruins deep in the Pennsylvania woods are thought to have been a ski lodge or a speakeasy, but no one really knows.

Potential high level nuclear waste storage site for the next 10,000 years and beyond.

An ancient instrument used to measure the waters of the Nile so Egyptian farmers would know whether to expect famine or flood.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

The pits used to load the nuclear bombs onto the aircraft that dropped them over Hiroshima and Nagasaki at the end of World War II.

This network of tunnels housed an entire village for years, and even had a hall for screening movies.