A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

A once crucial portion of the Long Island railroad still lays abandoned, waiting to be turned into an urban park.

A collection of fanzines, recordings, and documents detailing the rise and influence of the feminist punk movement.

Just your average Marie Antoinette–themed speakeasy in an abandoned 19th-century subway tunnel.

A small peaceful park and waterfall tucked amid the urban grind of Midtown Manhattan.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

A Victorian cemetery in the heart of Brooklyn remains a popular mecca of morbid curiosity.

A hyper-luxurious, 12,000- square foot home might be buried beneath Queens, still waiting to protect you from nuclear missiles.

Cryptic messages embedded in the New York City sidewalk.

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.

Hordes of precariously balanced stone figures crowd the shores of the Hudson River.

A living archive of urban activism and space reclaimed.

Detailed facade of a brownstone in Boerum Hill.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

This former Norwegian sailor's church is slowly being taken over by ramshackle robot musicians.

Nondescript elevator doors open to reveal a stunning, surreal world.

The oldest surviving synagogue in New York City is now a soaring art space.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

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

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.