This Gold Rush ghost town was once the subject of a territorial dispute between California and Nevada.

The ruins of a military outpost from the 1860s form the centerpiece of a Nevada state park.

An abstract monument to a symphonic composer.

A subterranean house of worship carved right out of the bedrock.

A favorite with sightseers, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

One of the most breathtaking railways in Europe also takes one of the steepest climbs, from fjord to mountain plateau.

Home to three historic ships from the age of Vikings.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

This small stone building, the final work of a renowned artist, offers a peaceful environment with radiant, colorful glass windows .

The second largest roadrunner in the world stands 11 feet tall in his West Texas town.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

The outcropping is graffitied with the name of the beloved musical Muppet television series.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

In the past, Renaissance sex workers were encouraged to entice customers on this bridge.

Go inside to really appreciate this 500-year-old technological masterpiece.

Two stone columns flank the grand Venice square, but there were supposed to be three.

This deconsecrated church has seen many uses, from a tobacco storehouse to a cinema.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

This home designed for chocolate magnate Antoni Amatller is an exquisite treasure-box of Catalan Modernism.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.