The most remote tree in the world is more than 170 miles from its nearest neighbor.

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

A nearly unconquerable island-fort in the Indian Ocean.

The oldest still-inhabited hill fort in India looks like a magnificent golden sandcastle.

This hilltop warren of monastic dwellings is the result of centuries worth of Mongol attacks.

The Arctic Archipelago is home to world's largest third order island: an island in a lake on an island in a lake on an island.

The haunting beauty of this little-visited wreck makes it a true hidden treasure.

Featuring the last fully walkable parapet walkway in Europe.

Surrounded by a smudge of dark earth, this isolated volcano sits in stark contrast to the surrounding Sahara.

A fifth-century temple improbably built into the side of a cliff.

This vertical pinnacle in China was the inspiration for the floating mountains in the movie “Avatar.”

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

This lovely little bridge hidden in a Switzerland gorge is essentially a fairytale.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

A stunning hermit's shrine on a steep rocky spur in Northern Italy.

This church carved into the rocks is full of enchanting stone statues.

This ancient altar emerges from the thick forests to reveal the mysteries of Etruscan sacrificial rituals.

Over 100 towers were built in Bologna during the Middle Ages, but only 22 survive.

People have been living in the cave houses on this Italian hillside since the Neolithic era.

Southern Italy's spinning top village.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

This Tuscan lake hides a 13th century town that is still visible when the water recedes.

This medieval Italian town is a sheer (and beautiful) cliffside defense.