This pristine World War II airfield gives a comprehensive look at atomic development and aviation history.

Oregon's only closed-basin hypersaline lake, an important stopover for migrating waterfowl, is in danger of drying up completely.

This 19th-century zoological collection has withstood the test of time.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

This mysterious petroglyph evokes the ancient swastika symbol but was later vandalized with the more troublesome Nazi one.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

This Parisian gem is one of the most incredible ethnographic museums in the world.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

The curious underground history of keeping Paris clean.

A modern-day Lascaux cave underneath Paris.

Museum on French naval history, with magnificent figureheads, a historic diving suit, and a boat used by Napoleon.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The Sun King's military models, saved from the Louvre.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

A giant statue perched on dumpsters watches over the freeway.

A gathering of green robots at the Googleplex.

In 1998, Larry Page and Sergey Brin briefly ran their fledgling company from this Silicon Valley garage.

The only home that Alexander Hamilton ever owned has a history almost as troubled as his own.

This giant boulder is sandwiched between apartment complexes in upper Manhattan.

This was one of the first (and last) university-built and operated nuclear reactors.

Historical figures from New York City's Catholic community reside in Midtown.

A local prank turned town icon.

In the Ozarks, a waterfall shoots out from a glorious hole.

This large chunk of dark rock is a relic from an ancient volcanic eruption.