This 3,800-year-old site contains markers used to study the movement of the sun and moon and create a lunar calendar.

This giant Buddha statue has 125,000 smaller Buddhas hidden inside it.

This odd museum/art gallery embraces the physiological, zoological, and ethnographic side of sex.

Mongolian Buddhists believe this monastery in the Gobi desert to be the center of the world's spiritual energy.

This fairy-tale, neo-Gothic church in the Azores is a world of magical realism.

A dark tunnel leads to a striking white crater that seems to be from another planet.

Once home to Komodo dragons, this island dreamscape has a rare combination of white, pink, and black sand beaches.

This abandoned fishing settlement may well be the greenest village in the world.

More than a century of radio history is told in these displays.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

A rapidly disappearing glacier filled with extinct grasshoppers, perfectly preserved in the ice.

A petroglyph map of the upper Snake River carved by prehistoric hunter-gatherers.

South Africa's postal service began with a letter left in a boot beneath this tree.

This rare volcano spews the strangest and (literally) coolest lava in the world.

The world's oldest bookshop still in operation.

An ancient instrument used to measure the waters of the Nile so Egyptian farmers would know whether to expect famine or flood.

A Jenga-style cylindrical tower of books that appears to go on forever.

Six beautiful wooden giants are hidden around Copenhagen.

This stunning natural double arch, the largest in the Alps, went undiscovered until 2005.

The architect of this fanciful complex called it an "oasis for humanity and nature in a sea of rational houses."

One of the largest-ever mental hospitals now sits abandoned, surrounded by 25,000 unmarked graves.

The pits used to load the nuclear bombs onto the aircraft that dropped them over Hiroshima and Nagasaki at the end of World War II.

From Coke II to Google Glass, this exhibit features some of the most spectacular commercial flops.

The reason for the strange contortions in the trunks of these "drunken" pine trees in Russia is still a mystery.