These numerous Israeli caves were dug out over hundreds years for reasons ranging from hideouts to burial sites.

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

In the middle of downtown Brooklyn lies a 165 year old secret hidden right below the surface (closed to the public indefinitely).

Hear the tales of New York's most notorious criminals.

Built as a gift to the hottest tastemaker of the time, these hidden quarters remain an Art Deco showpiece.

The only home that Alexander Hamilton ever owned has a history almost as troubled as his own.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

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

Ride the subways of yesteryear.

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

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

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

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

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

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

Elevated freight railway turned wildly successful urban park.

New York's oldest magic store.

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

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

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

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

These whimsical works of art tell the story of the city's past and present.

This small glass cube is a peaceful out-of-the-way sanctuary at the busy airport.