Houses are tucked between, on, and underneath giant boulders.

Tucked away amidst some of the most famous addresses in the world is New York's only fraction of a street.

A historic observatory precariously perched at the "Top of Europe."

Everyone's favorite clay duo immortalized in bronze.

Banished from town, this local jester concocted a clever return.

Take a ride back in time with a steam locomotive trip through Eritrea’s mountainous countryside.

Pilgrimage site for star-crossed lovers.

Located more than 600 feet beneath sea level, this tunnel boasts the world's first undersea roundabout.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The Kalamazoo factory has 100 years of instrument-making, and one big wartime secret.

This reconstructed Norman castle is the world's most accurate, from location to livestock.

The second-longest continuous wall on the planet protects a hidden secret in the deserts of India.

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

A mysterious shape catches the eye in this 16th-century painting.

The lighthouse central to the 1980s horror classic "The Fog" is, in fact, located in one of the foggiest areas of the Pacific Coast.

The 700-year-old fortress was the site of Count Orlok's castle in "Nosferatu."

Six tiny houses built for working class people form the largest intentional cluster of Wright homes anywhere.

With a floor made of thick glass, this observation deck offers a full view of Sunwapta Valley's mountains and rivers.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

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

Where condemned pirates met their grisly end at the gallows on the River Thames.

One Portuguese poet described this cape, the westernmost point in mainland Europe, as "where the land ends and the sea begins."

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.