These mouldering mansion ruins remember a time when the Catskills were nothing but luxury.

A forsaken wonder in the middle of the East Side neighborhood.

A recently abandoned psych ward at the end of Sanatorium Road.

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

A beautifully designed asylum was resurrected as a hotel and art center with a ghost story or two.

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

This Central New York ghost town was once a prosperous railroad community.

An abandoned Gold Coast-era mansion once intended for the exiled ruler of Albania, who never arrived.

A crumbling hospital from the 1850s on Roosevelt Island.

Tucked in the back of this amazing antique store is an important piece of medical history.

All that remains of a magnate's dream home is a historic gate and an abandoned public pool.

This abandoned dream castle and its cemetery look out over the city that once inspired their creation.

This abandoned psychiatric hospital once housed more than 4,000 patients in the middle of a quaint New England town.

Underground tunnels remain beneath this abandoned mental asylum.

Ruins of a historic medical facility sits eerily by the water.

An eerie, decaying ghost town destined to fade into the forest.

A religious-themed park filled with folk art to bring biblical stories to life that fell into disrepair and now being restored.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

The largest burial mound in the United States holds the remains of prehistoric West Virginians.

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

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

Hundreds of numbered stakes hidden in the woods mark the graves of the lost souls of a nearby asylum.

This forgotten graveyard in rural New York State once served a pioneering hospital.

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