While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Look closely and you’ll notice that the color changes a third of the way up the tower.

The "lovely red Vega" of the legendary record-settling pilot.

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

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

A nostalgic bibliographic gem.

The walls of the iconic dome are hollow and have a secret stairway.

A museum honoring Oklahoma military service, where you can look into Hitler's mirror and see a Mickey Mouse gas mask.

American bison herd descending directly from a Bronx Zoo breeding program that saved the species from extinction.

This otherwise unremarkable ski town building marks the site of Butch Cassidy's first robbery.

These colossal desert barcodes have been fine-tuning spy satellites for decades.

The awe-inspiring ship from the golden era of cruising has an incomparable history and a reputation as one of the world’s most haunted places.

Recently restored menagerie of Victorian-era beasts.

The final resting place of soldiers' loyal canine companions.

This little-known collection holds everything from "Dracula" notes, to the manuscript of "Ulysses," to the forged works of Shakespeare.

The collection is housed in an exquisite mansion that makes you feel like you've been transported to an Italian villa.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

A giant roundabout made up of six smaller roundabouts can befuddle the uninitiated.

The largest land animal skull ever discovered.

The highest bridge in America was built for an almost unnervingly small amount of money.

Single runway interrupted by a busy road that cuts across its middle.

A collection of decorative eggs to admire in the off-season.

A Black Forest cuckoo clock theme park features one timepiece big enough to walk inside.

The site of Paul Revere's historic two lantern warning.