This haunted hotel built on natural springs once served as a hospital for a quack doctor promising a cure for cancer.

Cliffs that hold fossils, including the earliest known reptile, dating back more than 300 million years.

At 8,000 feet, the world's highest tea estate draws visitors for both its products and its panoramic views.

Old Danish castle immortalized in Shakespeare's Hamlet.

The forbidden island of the Tuscan Archipelago may still contain buried treasure.

Africa's Venice on stilts.

Unexplained bald patches in the landscape grow and recede over time, as though they are somehow alive.

Long abandoned underground complex to keep royals safe from a nuclear war that never came.

Small Island off the coast of Greenland.

The hermits of Karoulia protect their asocial lifestyles by living on the vertical face of a treacherous precipice.

The once highest point in China blends symbolic design with a kick of adrenaline.

For those with no fear of heights: a skywalk 4,700 feet up on a Chinese mountain.

New Zealand's epic shrine to all things puzzling.

A total of 999 stairs lead visitors through a massive hole in a mountain known as the Gateway to Heaven.

The world’s tallest outdoor lift stretches along the stone pillars that inspired the floating mountains in the movie “Avatar.”

This terrifying glass bridge on the side of a mountain cracks as you step on it.

The latest in a series of long glass bridges suspended at terrifying heights.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

The villagers of the coldest inhabited place on Earth adjust to unique challenges presented by day-to-day living.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

Popular tourist destination where witches in dark hats sell dried llama fetuses for good luck.

A meandering boardwalk across the bogland leads to a "stairway to heaven" with sublime views.

The world's tallest palm trees look like the whimsical kind of plant you'd find in a Dr. Seuss story.

A boardwalk winds above this beautiful bog full of wildlife and a rare type of turtle.