A reproduction of earth's many biomes.

This geothermal hot spring hides beneath a slowly growing mineral dome.

Carved by a waterfall in a hard-to-reach rock formation, this heart-shaped rock has inspired romantics for decades.

Welcome to old Florida, where a 1940s mermaid show is still enchanting visitors.

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

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

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

It's not hard to see why the historic Peabody Conservatory of Music's library has been described as a "cathedral of books."

The world's longest known cave system.

Florida might be at its most surreal in this museum devoted to the famed Spanish artist.

A modernist landscape of water and sci-fi concrete.

A museum dedicated to the alleged Roswell Incident.

Where manatees are the snowbird vacationers in these balmy Florida springs.

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

Tiki luxury on Nob Hill.

Take a drunken tour inside the world's largest known geode.

One person's lost luggage is another person's treasure.

Each year these high desert hills are absolutely covered with poppy flowers in a surreal show of nature.

A lush green oasis in the middle of Chicago.

This incredible collection of vintage pinball machines can be played at 25 cents a pop.

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

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

A huge musical sculpture and other art installations on the National Oceanic and Atmospheric Administration grounds.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.