A reproduction of earth's many biomes.

Rippling sand dunes frozen in the Arizona rock.

The highest bridge in America was built for an almost unnervingly small amount of money.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

The lush coastal city of Astoria is riddled with forgotten secret sidewalks.

The longest navigable underground river in the United States is home to countless blind and albino animals.

The longest living non-clonal organisms on Earth.

A natural gas leak provides a flickering flame beneath a waterfall.

An unfortunate geological resemblance to Satan has labeled this Pasadena gorge as a passage to the underworld.

The remains of the first punk club in L.A.

Tucked in a nondescript downtown Brooklyn mall is a bar containing a remarkable turn of the century anatomical wax collection last seen in 1920s Berlin.

This lake in the Cascades lives up to its name, disappearing down a hole every spring.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

Sail through this subterranean show cave that is home to a legend that would go on to name nearly everything around it.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

An homage to everyone's favorite prehistoric cartoon family.

A house carved into a rock in the 1940s.

One man's ambition created this psychedelic log home.

An extraordinary mixture of natural beauty and man-made phenomena.

European castle ruins in an American state park are actually the product of death and grief.

This rugged area of red rocks and arches is often considered one of the most beautiful places on Earth.

This "zoo" is a cross between a junkyard and a sculpture garden, featuring animals you won't see anywhere else.

This ruined fort hidden at the top of Central Park can't seem to keep from losing its historical plaques.

An outdoor sculpture park of giant pink robots and post-apocalyptic Christmas scenes.