A cave in southern Italy adorned with thousand-year-old Biblical frescoes existed in obscurity until fairly recently.

An eccentric 18th century naval officer built a ship's quarterdeck on his roof, the inspiration for Mary Poppins's "Admiral Boom."

A mysterious spot where the laws of gravity seem not to apply.

The final resting place of the camel who served with the Confederate Army during the Civil War.

The nude sculpture on this fountain shocked conservative townsfolk when it was first unveiled, but not as much as the dead body found in it decades later.

Twice a day this ancient path disappears with the tides, leaving the Holy Island of Lindisfarne out to sea.

This abandoned school has had many lives since the early 1900s, and all of them doomed.

The abandoned grounds and derelict greenhouses of this once-magnificent Edwardian estate are now a nature preserve open for exploration.

The Cambridge pub where Francis Crick announced that he and James Watson had discovered the DNA double-helix.

Unusual hexagonal rocks formed by cooling lava named for their resemblance to traditional Japanese tatami mats.

The library's graceful rotunda is like a bibliophile's temple.

Guests can stay at a hotel in the former French abbey where lie the tombs of King Henry II and King Richard the Lionheart.

Iceland's largest geothermal mud pool is a little bit haunted and a little bit dangerous.

An absolutely beautiful 200-foot stained glass installation traces the evolution of knowledge.

The discovery of this Neolithic settlement, which contained a Stone Age "cathedral," threw archaeologists for a loop.

A stone in Wolin, Poland, marks the possible location of a legendary Viking fortress.

This modern arts center is built around a gem of late-Baroque architecture.

The ruins on a deserted tropical island in the Philippines bear the scars of WWII.

The streets of a sleepy Spanish town proudly exhibit some of the world's finest graffiti.

The walls of the iconic dome are hollow and have a secret stairway.

They sort through millions of dollars worth of diplomatic gifts on behalf of the government.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

A modern-day Lascaux cave underneath Paris.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.