An abandoned water sports stadium that has become a haven for graffiti and decay.

This abandoned prison castle has become an imposing gallery of graffiti art.

Unlike other abandoned asylums this empty institution welcomes visitors, just don't go in the buildings.

This lovely university observatory continues to sit abandoned since its potential savior was sent to jail for fraud.

This Queens hospital has stood abandoned for almost 20 years after its patients were secretly relocated in the dead of night.

This Cold War siren is one off the last of its kind still standing with its immensely powerful original horn.

What was once one of the country's largest confectionary plants is now an abandoned ruin, but is still pretty sweet.

The ruins of a cotton mill that was burned in the Civil War are still hidden in a Georgia forest.

What was once the second largest steel mill in the US is now a sprawling complex of modern ruins.

This huge, disused viaduct is now a crumbling concrete underworld of covered in years of graffiti.

The remains of a failed subway in upstate New York is now an underground graffiti bunker.

The ruins of a Massachusetts prison farm can still be found crumbling the woods of a state park.

The cruel trial of a 13-year-old boy inspired the creation of this now abandoned reformatory.

This abandoned bootleg attraction was built to cash in on the popularity of classic TV show, F Troop.

A former zoo turned public park, where visitors can hang out in the old animal cages.

The bears may be gone, but their old cages can still be found.

This mouldering abandoned mental hospital was once a center for progressive healing.

From overly ambitious (and eventually abandoned) atomic dream to bustling office park.

This abandoned subway station can still be seen on regular commuter trips.

This once bustling boomtown hotel is now the hottest spot in Nevada for ghost hunters.

Instead of becoming a power plant, this abandoned complex became a massive letdown.

One man's ambition created this psychedelic log home.

A key producer of charcoal iron in the early 1800s, the structure still stands today.

This abandoned ironworks was once the most important military supplier in America.