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

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

Collapsing castle on the Hudson river was once the storage site of military surplus business.

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

Become a prohibition rebel.

One of New York's best collections of pinball is hidden in a secret bar in the back of this laundromat.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

A DIY art gallery/music venue/lecture hall dedicated to video game culture.

A hip bar decorated with walls of golden skulls.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

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

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

A semi-scholarly approach to sex.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

A crumbling hospital from the 1850s on Roosevelt Island.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

A huge musical instrument played by the ocean.