This statue honors the thousands of Allied avians that served and died for France during World War I.

Museum in a swimming pool where the water still flows.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

The last bastion of Roman presence north of the Alps looms over a German town.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

Once the local rulers had gone these enchanting ruins housed common folk in an almost real life fairy tale.

Dedicated to the American general whose reply to a German demand for surrender was simply "Nuts!"

Rare wooden escalators lead deep down into an otherwise staggeringly monotonous tiled tunnel.

According to this bar, God gave an “11th commandment” to Antwerp: Thou shalt drink beer.

The patron of this extravagant Art Nouveau confection insisted that nothing less than a boat should project from its facade.

A ruined castle stands atop a hill surrounded by dragon lore.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

The fairy tale castle of the “fairy-tale king,” this was also the inspiration for Disney’s “Sleeping Beauty.”

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

This massive Brazilian church is built like an angular, technicolor pyramid left by Mayans from the future.

Eduardo Kobra’s breathtaking 32,300-square-foot graffiti wall took over Rio’s Olympic Boulevard.

The final resting place of the cats that once belonged to a Brazilian actress.

A 125-meter long "tribute to the Brazilian people."

Crumbling remnant of Rio's colonial past tucked behind Corcovado mountain in the neighborhood of Cosme Velho.

This Brazilian town built by Freemasons is full of colonial Masonic architecture and symbolic imagery.

The bones of the Biblical Magi traveled to Constantinople and Milan before landing in their current home inside an elaborate golden reliquary in the Cologne Cathedral.

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.