A crumbling hospital from the 1850s on Roosevelt Island.

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

One of only two commuter aerial tramways in the United States.

A sculptural commentary on capitalism pokes up from the East River.

A former insane asylum despised by Nelly Bly and Charles Dickens is now fashionable apartments.

Home to the infamous "Typhoid Mary" and the worst loss of life in New York's history prior to September 11, 2001.

The first and only carousel with a lineup entirely of insects.

Mysterious 500-year-old tapestries depict a unicorn hunt.

The famous author's cottage hideaway.

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

A beautiful, historic location open to the public.

America's greatest forgotten garden and the former stomping grounds of Son of Sam.

A miniature village lies nearly forgotten in the forest by the side of a major highway.

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