This beautiful building in the heart of Manhattan's Financial District was empty for decades.

Abandoned railway line circling the city of Paris.

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

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

A psychedelic labyrinth on the San Francisco bay.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

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

It should come as no surprise that the best view of the Hollywood sign is from Batman's lair.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

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

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

Rippling sand dunes frozen in the Arizona rock.

This massive library holds what was once the largest book collection in the world.

A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

Most-visited and most-photographed slot canyon in the American Southwest.

A beautiful 62-acre Catholic shrine and botanical garden.

Oakland's beautiful monumental cemetery.

Dramatic river bend surrounds a natural red-rocked pedestal.

This stunning sea creature-shaped home blends into the landscape like a fantasy villa.

A miniature Italianate fantasy village on the coast of Wales and the set of ITC classic "The Prisoner."

Miniature art that tells an enormous story.