Light still pours into the ruins of this ancient Islamic observatory.

The curious underground history of keeping Paris clean.

Books bound in human skin and H. P. Lovecraft's letters are among a few of the treasures this library has to offer.

1513 Turkish world map, full of European state secrets and snarky commentary.

A hundred and twenty year old twelve story lighthouse located on a beautiful Indonesian island.

Quirky Welsh observatory unites art and science.

The largest traditional Chinese medicine market in the world sells ingredients that may make you squirm.

Every year, over 25,000 monarchs overwinter in Pacific Grove.

Be a ninja - or just act like one.

A house built from trash known as the poor man's Hearst Castle.

These subterranean storage areas hold emergency water reserves.

A tiny church on a man-made island in the Adriatic.

A gallery of underwater art that can be visited by man and fish alike.

Walk behind a 50-meter-high waterfall.

The Bristol Camera Obscura housed in an ancient windmill.

The fossilized remains of ancient California redwoods.

A large instrument played by the wind.

Micro-nation based around a nine-story high illegally built tower.

Enormous pendulum helps keep Taiwan's tallest building from swaying.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Dig for your own trilobites in this goldmine of invertebrates.

Experience Larry Spring's self-taught "common sense" laws of physics.

Nationwide network of co-ownership underground catastrophe shelters.

A 550-square-meter micro-nation off the coast of Britain.