A winding path built in secret on the edge of the continent.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

A giant Troll lurks under one of Seattle's oldest bridges.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

An emerald-green grotto just a short trip from Austin.

An artsy hidden staircase leads to breathtaking views of San Francisco.

A huge musical instrument played by the ocean.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

The celebrated eyesore created by starry-eyed sweethearts.

The video game-themed street art first popped up in the French city.

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

This surreal statue brings a famous French novel about a supernatural cad to arresting life.

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

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

This Parisian gem is one of the most incredible ethnographic museums in the world.

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

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

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