This skewed English house has looked like it's going to fall over for centuries.

The largest of London's subterranean rivers and once a mad, bad center of London life.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

This half-forgotten fortress was constructed by the Ottoman conqueror of Constantinople.

This historic hotel preserves many treasures from its heyday hosting passengers on the Orient Express.

A marvel of Byzantine engineering under the streets of Istanbul.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Eat the ultimate iteration of Portugal's most beloved pastry.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

An unassuming London park is actually a pilgrimage site for modern clowns.

A grand Gothic Revival basilica with stained glass depictions of Montreal's religious history has only one soul resting in its crypt.

Semaphore saints, a golden dragon's head, and a stone carved with religious warnings all call this cathedral home.

Follow the original medieval paths that wind through this intriguing section of the city.

This early Norman castle was the first historical monument protected by an act of Parliament.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

This 1920s Dutch barge is now a floating bookstore.

This morbid, delightful curiosity shop offers everything from animal bones to human teeth.

The world's largest reflecting pool is just two centimeters deep.

This mountain trail inspired Nietzsche to complete his magnum opus.

This saucy statue once caused outrage among locals.

The final resting place for the remains of 143 Habsburg royalty.

Roughly 17 million letters to Santa have found their way to this Arctic Circle post office.

If you visit Santa's village, you can get your passport stamped to show you crossed into the Arctic Circle.