An underground city of salt.

This lesser-known Frank Gehry building houses a treasure trove of cinema history.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

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

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

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

Notorious artist squat renovated into legal studios.

A massive collection of petroglyphs dating back some 40,000 years.

This mysterious but iconic tapered tower appears in many Azeri fairytales and legends.

A gigantic collection of teeny, tiny books.

Mysterious hillside with a continuously burning natural fire.

Foreign invaders almost left this lovely Caucasus palace alone—almost.

A quirky house created entirely out of glass bottles combines a collector's spirit with an artist's flair.

Home to nearly a third of the world's mud volcanoes, Azerbaijan is home to a messy, bubbling, and sometimes explosive landscape.

A unique museum dedicated to culture and artistry of carpet weaving.