A miniature train-ride through Slovenia's largest cave system.

A whimsical bridge adorned with decorative dragons.

This one-time health resort was used by aristocrats around the world.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

One of Frank Lloyd Wright's greatest—and favorite—architectural masterpieces was almost lost.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

The heroic sled dog of the 1925 serum run is preserved in taxidermy.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

The home, museum, and death site of Kodak's influential founder.

"Call for the doctor, call for the nurse... Vote!! said the lady with the alligator purse."

Comprehensive gaming collection of over 30,000 electronic games and consoles.

One of the great math minds of the 17th century is underfoot in this 900 year old Dutch church.

Now a museum, this building was once a 14th-century monastery and the place where the founder of the Dutch nation lived and was assassinated.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

A Texas museum filled with Broncos and Betties.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

An astounding collection of medical specimens, including bits of President Lincoln.

Monument to a suicide protesting the Soviet invasion.

A hugely vast Irish landscape of barren rock that stretches for miles.

Elvis's own personal tropical hideaway.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

Belly up to the bar in Cowtown, don't forget to buy some boots.