The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

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

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

Hellam Township is reputed to feature seven remote gates, which when passed through in the right order, open an entrance to hell.

Read a book next to a Midtown waterfall.

An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

The inspiration for H.P. Lovecraft's horror stories and Batman's Arkham Asylum is now a condominium complex.

Enormous lake at the bottom of a unique cave system.

A hand-built folk art installation covered with messages of God's love.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

The only theatre in the world constructed specifically for sound movement.

A toxic ghost town sitting atop a massive coal fire.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

World's first "penitentiary," meant to be humane, drove men insane.

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

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

A crumbling hospital from the 1850s on Roosevelt Island.

A snapshot of the city's fascinating voodoo culture.

Tucked in the back of this amazing antique store is an important piece of medical history.

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

A terrific purveyor of natural history objects and curios.

A forgotten monument to Yugoslavian freedom.