High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

A 140-year-old castle with underground caves hidden in San Francisco.

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

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

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

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

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

An enormous, inside-out glass globe built in 1935.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

Dramatic river bend surrounds a natural red-rocked pedestal.

On Japan's Tashirojima Island, cats are king.

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

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

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

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

An eerie, derelict amusement park in Berlin.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.

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

A magical place that lets you play in and explore the world of Studio Ghibli.

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

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

A crumbling hospital from the 1850s on Roosevelt Island.