The history and future of cannabis.

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

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

An underground city of salt.

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

Krakow's own version of the Hollywood Walk of Fame.

"Holy Wisdom" overlooks the city that became its namesake.

Sofia's legislative center is continuously reinventing itself.

This building has two facades of clashing architectural designs.

A striking symbol of the Bulgarian capital.

This futuristic German television spire is actually the world's largest digital clock.

While you wait to cross the street at a traffic light in Mainz, you might notice that the light is staring back at you.

A little sculpture with a large wardrobe.

Meet the bronze beloved pet to a family of famous peeing statues.

An early 20th-century bullring converted into a modern shopping center.

32,000 tiny soldiers are posed in 23 historical settings.

This religious complex carved into a cliff is steeped in legends of miraculous stags and the Holy Grail.

The final resting place of the famed German pilot, the "Red Baron."

Fantastic views and thousands of love locks.

Somber memorial to the May 10, 1933, book-burning which took place on this spot.