An abandoned horticulture institute gloomily presides over rows of derelict and vine-wrought greenhouses.

The haunting, dilapidated remains of a former poorhouse on Staten Island's Greenbelt.

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

This forlorn park is the result of a failed investment turned tax dodge.

The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

The abandoned ruins of America's first private zoo are open for exploration in the Catskills.

A forgotten relic from New York's bygone trolley system hides in plain sight under a bridge.

The remains of what was once the world's steepest passenger funicular.

The final resting place of some of Staten Island's earliest settlers and their descendants.

The abandoned grounds and derelict greenhouses of this once-magnificent Edwardian estate are now a nature preserve open for exploration.

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