Before serving as James Bond's Casino Royale, this Victorian-era spa catered to the world's elite.

An ornate plague column – built to celebrate life – claimed the lives of numerous artisans during its construction.

Street artists transformed an abandoned air vent into the beloved Star Wars robot.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

Europe's second largest ossuary wasn't discovered until 2001.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Countless grotesque faces stare out from this eerie Prague art wall.

A Jenga-style cylindrical tower of books that appears to go on forever.

Macabre astrological automaton clock dating to the late 1400s.

Two stunning 17th-century libraries and a cabinet of curiosities.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

A church of bones, decorated with 40,000 human skeletons.

A marvel of Byzantine engineering under the streets of Istanbul.

No one is sure if the world's fourth-largest diamond had been found in a rubbish heap or was pawned by Napoleon's mom.

A hidden alley in urban Baltimore is a haven for graffiti artists.

What was once a presidential estate is now an exotic menagerie and home to the Budweiser Clydesdales.

Less a museum than a bizarre fantasy world created by artists and engineers.

The red brick house where the father of rock 'n' roll wrote some of his classic hits.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

The oldest operating Mississippi River–style steamboat still navigates the Ohio River.

The grave of the iconic Kentucky Fried Chicken mascot features a bust of the man behind the goatee.