An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Paris' linguistic guide to the international language of, yes, love.

One of the oldest medical collections in Europe focusing on rare surgical instruments.

Abandoned railway line circling the city of Paris.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Notorious artist squat renovated into legal studios.

France's most famous cemetery, with some of its most curious tombs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This temple to the sturm and drang of Richard Wagner contains a dragon's cave and reptile zoo full of living "dragons."

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

This small condiment museum makes all manner of mustards with a 200-year-old mill.

This little jewel of post-war religious architecture is hidden inside the Diocesan Museum, which swallowed it when it was built.

This 19th-century fountain features sculptures of little gnomes that help with chores.

Life-sized bronze statues of fictional puppet characters.

The largest mosque in Germany.

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.

A poignant mural honors the heroic teenage non-conformists who took on the Nazis and paid the ultimate price.

If the tunes of antique organs and musical marionettes don't intoxicate you, the draft beer certainly will.

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

How did a lighthouse wind up in the middle of this landlocked German city?

This "floating railway" is one of the world's oldest monorail systems.

The monumental home of Prussia’s eccentric "Cannon King."

Be it nature, art, or abandoned military architecture this eclectic German "museum" has you covered.