The ruins of an ancient island city built atop a coral reef in the South Pacific are spectacular and strange enough to have inspired H.P. Lovecraft.

A neutrino detector built into the largest man-made underground cavity in the world.

The site of one of Japan's very few American occupations during World War II still holds the relics of a roundly disastrous campaign.

A curious collection dedicated to human and animal anatomy and pathology.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

This 17th-century street hidden beneath Edinburgh was once a breeding ground for the black death.

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

It should come as no surprise that the best view of the Hollywood sign is from Batman's lair.

An eerie, derelict amusement park in Berlin.

A church of bones, decorated with 40,000 human skeletons.

The fairy tale castle of the “fairy-tale king,” this was also the inspiration for Disney’s “Sleeping Beauty.”

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the first ‘Harry Potter’ film.

Medicinal spa created from the mineral-rich runoff of a geothermal power plant

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

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

The very first subway station in New York City is beautiful, decked out in chandeliers, and ... abandoned?

Submerged ruins of a Neolithic coastal settlement, where houses, wells, graves and skeletons have been unearthed.

This subterranean funicular is one of the world's smallest subways.

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

The world's only official college program focused on "clown therapy."

One of only two towns in Israel populated by Circassians, a sect of Sunni Muslims who are also devoted to Israeli military service.

As the Dead Sea continues to deplete, massive sinkholes open along its banks.

These numerous Israeli caves were dug out over hundreds years for reasons ranging from hideouts to burial sites.