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

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

An eerie, derelict amusement park in Berlin.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

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

On the Oregon coast there is a natural hole that seems to be draining the sea.

A crumbling hospital from the 1850s on Roosevelt Island.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

Rippling sand dunes frozen in the Arizona rock.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

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

This once-palatial plantation may have been the site where a draft of the Declaration of Independence was written.

The angel of death appears to weep black tears at this grave marker.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

Once an ambitious nature spa, these forest ruins now provide a serene monument to failure.

Sister store to the Echo Park Time Travel Store.

A prohibition-style speakeasy takes up residence in the last Victorian residence in Hollywood.

This abandoned ironworks was once the most important military supplier in America.

Vietnam's feral abandoned water park offers access to a post-apocalyptic funscape, now with fewer crocodiles.

A late sculptor's last project was to turn this abandoned cement factory into a castle-themed amusement park.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.