The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

The dairy farm in upstate New York where nearly half a million people gathered for three days of peace and music in 1969.

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

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

This once sprawling resort now sits abandoned, filled with graffiti and vibrant colors from an era long passed.

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

American artist J. Alden Weir purchased this 60-acre estate for $10 and a painting.

Mansion and shopping center used in the 1975 film "The Stepford Wives."

Forgotten under the construction of a new urban roadway is a small, abandoned part of town.

A once-booming railroad left abandoned next to the Quinnipiac River marshes now intersects with a hiking trail.

This historic park site contains the last remnants of a once bustling canal system.

Edison's cast-in-place concrete houses were a failure, but way ahead of their time.

This tiny New Jersey village has lived many lives but seems determined to remain a ghost town.

An allegedly cursed tree represents a town's reckoning with a racist past.

This elaborate towering structure was once famed for its revolutionary height.

This factory made "health corsets" that were a step towards liberating women's bodies.

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

This picturesque abandoned home is rumored to be a spite house.

This small stone chapel is a hidden gem just outside the University of New Hampshire campus.

Accessible only by boat, this centuries-old island fort never saw troops or combat.

The only remaining historic maritime signal station in the United States.

The world's only international cryptozoology museum is host to an unrivaled collection of mysterious objects.

Abandoned Italianate architecture on the coast of Maine.

An abandoned Victorian-era mill in the middle of modern Manchester.