From Iggy Pop to David Bowie to Nick Cave, this regal music studio has served some of the all time greats.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

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

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

A Belle Epoque bordello turned into a themed love hotel.

This recessed garden protects thousands of mountain plants by creating its own microclimates.

An immersive projection art installation uses sound, scale, and light to take visitors inside classic works of art.

An iconic and eccentric bar for "Manouche" Jazz music keeps expanding its space—and its influence.

An off-the-beaten-path boutique stuffed with an eclectic collection of upcycled goods.

Noirish green neon marks the location of one of the oldest private detective agencies in France.

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

Original cabaret handbills, posters, and feline artwork are a purrfect highlight of the Museum of Montmartre.

This Parisian fountain is a little bit fantasy and a little bit nightclub.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

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

Abandoned railway line circling the city of Paris.

A medieval military street hidden beneath a charming French fishing village.

Artist's eccentric property excessively decorated with found objects and work of his own.

An Orthodox church built by the Royal Family for the Russian community exiled to the French Riviera.

This architectural onion has an original 1930's Jerry O'Mahony dining car at its core.

This massive solar system model is sprawled out across Maine's suburban wilderness.

This candy-striped tower is the farthest east you can go in the United States.