Early prototype for Frank Lloyd Wright's Guggenheim.

The once-abandoned 140-year-old hotel used in the movie "In Dreams."

A defunct all-girls college which may be the resting place of H.P. Lovecraft's real-life Necronomicon.

A monster in the plant world, up to 10 feet tall and smelling of death.

The sign at the garden gate reads: "These Plants Can Kill."

The show pony of cave systems, Fantastic Caverns manages to live up to its name.

Christ's blood preserved in a Belgian town.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

The anatomical-pathological collection of a man who changed surgery.

Two adjoining collections of 19th-20th century physics apparatuses and instruments.

Beyond being incredibly fun, not much can be said about the Hole with certitude.

The macabre graffiti spectacle in a quarry in a Massachusetts forest reservation.

A cave dug by a man directed by ghosts to find pirate treasure.

A museum dedicated to the exploring past, present, and future innovations.

A museum within a museum, devoted to history's most questionable medical devices.

Home to the Amorphophallus titanum "Corpse Flower," which is among the largest flowers in the world and also smells powerfully of rotting flesh when in bloom.

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

Remnants of a storybook amusement park hidden behind a strip mall.

Take a drunken tour inside the world's largest known geode.

An eccentric inventor's castle home with its own indoor weather system.

The once abandoned ruins of a Victorian beachside amusement park are now back in working order.

The intriguing personal collection of a professional demon-chaser.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

The rocks in this arid basin leave trails of movement behind them.