A hidden "place of interment for gentlemen."

A terrific purveyor of natural history objects and curios.

A curious fountain that has no water and includes Satan, a crab, and 9 giraffes.

A Natural History and Science Emporium.

Relics given to a Manhattan church to avoid seizure by the Italian government.

New York City's only preserved family home from the 19th century.

Surrounded by low rise buildings and partially converted into an auto body shop, this marble archway is the only vestige of a forgotten Manhattan estate.

Site of the first pathological and bacteriological research facility in the United States.

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

A WWI fighter plane and turn-of-the-century penny candy shop are among the unexpected features of this Financial District building.

New York's unstoppable progress turned this cemetery into the smallest burial ground in the city.

Once considered the height of medical modernity, this structure is now the oldest remaining component of Roosevelt Hospital.

A Manhattan Episcopal church with an eerie underground crypt.

The notorious headquarters of a corrupt political machine.

The greatest real estate coup of all time.

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

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

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

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

This humble historic facade hides a history of boozing and the gentlemanly sport of rat-fighting.

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

Amid the marketing blitz of modern Times Square is an elegant holdover from its showbiz glory days.

Captain America, Sub-Mariner, and the Human Torch were all born in this art deco Manhattan masterpiece.

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.