A historic 1890s architectural masterpiece with an iconic clock tower that, once open to the public, now faces an uncertain future.

One of the last few places in Manhattan that employed a pneumatic systemic keeps it on display.

The "Seinfeld" diner.

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

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

Great place to have a drink and a bite to eat in an atmosphere laden with New York's Bohemian past.

A very classy 1920s-era bar right in Grand Central Station.

The oldest operating apothecary in the US has treated everyone from Thomas Edison to Mark Twain.

Peek through the gates at this oasis from the city, full of Old English charm.

The name of this famed hospital was once a byword for the horrors of medical and psychiatric care.

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

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

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

A hands-on traveling collection of the innovative devices of yesteryear.

A legendary speakeasy bookstore returns from the brink.

Hidden in an ordinary Midtown building is a one-room museum dedicated to the greatest escape artist.

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

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

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

A dilapidated dock tells the story of Titanic's missed arrival.

A New York garbage depot holds a secret collection of weird and wonderful refuse.

This little museum is built on a theater that was once a wildly elaborate speakeasy.

A hip bar decorated with walls of golden skulls.

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