A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

Accessible only at low tide, the deserted island is dotted with World War II ruins.

A beautiful Greco-Roman structure houses a well once believed to have healing powers.

Protecting the dead from opportunistic body snatchers.

The most loyal of little dogs, or a Victorian era publicity stunt?

360° views of the city plus five floors of optical illusions and hands-on science.

This iconic 1,000-year-old medieval castle is a favorite of the film industry, most notably as the location for Hogwarts in Harry Potter.

Tucked in the back of a flower shop, its collection details the fascinating history of the Netherlands's iconic symbol.

This cheese shop also houses a museum devoted to Dutch dairy.

This pub boasts a curious history and may have inspired a Dickens character.

Chelsea's soldiers were given strict orders when crossing this historic bridge.

Pop culture has helped to keep this iconic British building from being destroyed.

A kaleidoscopic warehouse-maze of handmade neon signs.

This small village claims to be independent from Italy because it was left out when the nation was unified.

The medieval woodcut-style artwork chronicles life in medieval London.

A stunning hermit's shrine on a steep rocky spur in Northern Italy.

A stairway to heaven, or to nowhere at all.

Hidden in plain sight on a gable between two towers on the roof of shipping firm F. Laeisz' headquarter in Hamburg sits an unexpected bronze sculpture.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

Hamburgers are intensely proud of their tunnel beneath the river.

Hamburg's first legal sex work is relegated to a gated street that still does not allow pedestrian women.

This red light district plaza memorializes the Fab Four and their historic connection to the area.

A completely underground tour following the path of the most precious element: water.