The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

The remnants of an early American attempt at missile defense.

The 606 is a decade in the making.

The beauty of urban decay, hiding some dark secrets.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

A Beaux-Arts triumph set to become Ford's innovation campus

World's first "penitentiary," meant to be humane, drove men insane.

An abandoned bait shop with a front lot filled with storage boxes.

A small flooded ghost town with a few scattered structures remaining.

This former mining town was named the most toxic town in America.

Odd outsider art installations surround a Gold Rush-era ghost town.

An homage to everyone's favorite prehistoric cartoon family.

A classic roadside attraction on Vermont's historic Route 5.

Remnants of a storybook amusement park hidden behind a strip mall.

Destroyed by flood waters, prison now serves as a training ground for armed forces.

The once abandoned ruins of a Victorian beachside amusement park are now back in working order.

A stunning, abandoned limestone quarry in southern Indiana provided the stone to erect the Empire State Building.

The once-abandoned 140-year-old hotel used in the movie "In Dreams."

A late sculptor's last project was to turn this abandoned cement factory into a castle-themed amusement park.

This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

An abandoned munitions factory with a shot tower continues to wage war on the surrounding environment.

This abandoned motel doesn't welcome guests anymore, but decay and a creepy atmosphere still call it home.

The former locus of Boston's high culture has been shuttered and buried for over 70 years.

Undone by Prohibition, this abandoned brewery-turned-flour mill is now ready for its third act.