Once the most densely populated place in the world, this island is now a ghost town.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Site of a former hidden treehouse in New Orleans.

Continuing the tradition of the dime museum in style.

Since 1874, this macabre collection has developed into a museum devoted to Scotland Yard's mementos of dastardly deeds.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

This structure among the trees was the result of divine inspiration.

Mysterious rocks that ring musically when struck.

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

Towering basalt columns, a creation of fire and ice.

A spectacular cave and a beguiling lake.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

A strange house built only at night, with rumored mystic inspiration.

Hot springs monkey spa in the middle of Hell's Valley.

The legendary building that needed ghostly approval before being built.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

World's largest collection of serial killer artwork and other macabre exhibits.

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

A massive underwater sinkhole made famous by Jacques Cousteau.

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

A swing to dangle you off the very edge.

Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.

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