The location of the world's first telescope demonstration.

Hidden within a Netherlands crater is a stone bed that lets those who lie in it see the sky as a curved surface.

Germany's longest suspension rope bridge.

This former Nazi castle was built as a school to train what would have been the future of the Third Reich.

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

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

In this German city center, the streets have no names.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

One of few vertical lava tubes in the world accessible by foot.

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

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

Fantastic views and thousands of love locks.

The sweet story of how American cargo planes became known as "Candy Bombers" during the Berlin Blockade.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

It's good luck to be mocked by this monkey.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

This historic funicular system combines the old with the new while offering delightful views over the surrounding valley.

Only the face remains of this giant Buddha statue, which is said to be a source of luck for students.

An enormous pair of straw sandals woven in the traditional way—to keep demons at bay.

This enormous monument is one of the most iconic structures in Tokyo, rudely nicknamed "The Golden Turd."

This sprawling scenic burial ground is the final resting place of Japan's last shogun.

Next door to Tokyo DisneySea is a giant sculpture created by Taro Okamoto symbolizing the dynamism of life.

Losing lottery tickets are deposited at this shrine in hopes of better luck.

Sidle into a side alley for a taste of sumo wrestlers' traditional hot-pot soup, in a tiny restaurant founded by a former competitor.