The abandoned personal amusement park of the King of Pop.

The end of the 4 Line is also the end of the line for 300,000 souls in one of NYC's most illustrious cemeteries.

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

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

The loneliest island in New York.

A museum designed by and dedicated to P.T. Barnum in the town where he is buried.

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

Site of the first pathological and bacteriological research facility in the United States.

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

A tunnel once abandoned now thrives with graffiti art as an off-limits makeshift gallery.

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

The oldest continuously operating farm in New York State.

An eccentric playboy's astounding natural history collection.

A millionaire's abandoned swimming pool from the gilded age of one of America's most distinguished families.

Beneath the mossy overgrowth covering this once-sprawling campus lies decades of history and the secrets that come with it.

This massive underground salt mine now holds a sci-fi theme park in its depths.

A crumbling hospital from the 1850s on Roosevelt Island.

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

This turn of the century masterpiece has a mysterious goaty interloper.

You can still ride this 100-year-old work of art in Brooklyn's largest public park.

A Looff creation in Santa Monica best described as “a California-Byzantine-Moorish-style fantasy.”

A carousel trades in its classic horses and calliope for endangered species, native flora and fauna, and a modern soundtrack.

Three vintage horses survived a 1976 inferno and found a home on a sister carousel.

One of the few remaining carousels built by master amusement park carver Charles I.D. Looff.