A once grand hotel is being retaken by the wilderness it once capitalized on.

This once-grand marvel of engineering is now 41 miles of scenic hiking trail.

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

A mysterious, abandoned building rotting on the Brooklyn waterfront.

Discovered by cows, these upstate New York show caves are presented with a healthy dose of psychedelic folk art.

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

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

This once luxurious Catskills resort is now a haunting ruin.

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

This old cement mine has been used as everything from a mushroom farm to a recording studio.

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

An abandoned castle owned and ignored by Masons carries a cursed history.

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

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.

A deteriorating 1990s Girl Scout camp in a beautiful lush park on Lake Ontario.

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

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

The quarry was abandoned over 100 years ago, after a massive ammunition explosion ended in tragedy.