The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

A museum dedicated to the alleged Roswell Incident.

A pair of giant legs paying homage to a poem, a king, and it would seem, socks.

A clear blue swimming hole with hidden caves, still unexplored.

A sculpture made of 10 Cadillacs as a monument to the “Golden Age” of the American automobile.

The official atomic museum of the United States explores the explosive and productive history of a much maligned energy source.

This private residence was the template for one of the most beloved television homes of all time.

Guns that have been defending San Francisco since 1904.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

An "anarchical" no man's land, complete with garbage sculptures and a hobo-run "Landfillian Library."

Eastern zen meets Western grit in these four little trees growing out of a rock on Lake Tahoe’s Nevada shore.

Bits and pieces from the ill-fated Donner Party's winter cabins.

One woman's Viking Castle on Lake Tahoe.

The capitol city's oldest existing cemetery.

I Street Bridge is the heaviest swinging center bridge in the United States.

This 19th century train workshop is a treasure trove of railroad history.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

An awe-inspiring mosque in Morocco with one of the tallest minarets in the world.

Monument to a suicide protesting the Soviet invasion.

A mocking tribute to the past and modern leadership of Prague.

Looming communist pillar with a Czech twist.

A church of bones, decorated with 40,000 human skeletons.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

A marvel of Byzantine engineering under the streets of Istanbul.