Haven for steampunks.

This abandoned caretaker's apartment is one of 13 left in the New York Public Library system.

Come for the pastrami, stay for the million-dollar art.

This plot of old-growth forest is the largest surviving remnant of New York City's original woodland.

One of only two remaining Victorian-era greenhouses in New York.

Holding the most bodies of any cemetery in the United States.

The crown jewel of the Queens Museum is a nearly 10,000-square-foot architectural model of the city originally built for the 1964 World's Fair.

A hidden "place of interment for gentlemen."

This enormous Hindu temple in Queens serves incredible dosas in its basement canteen.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Unique antiquarian shop specializing in globes, maps, and prints.

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

The "Seinfeld" diner.

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.

New York City's smallest piece of private property.

World's first "penitentiary," meant to be humane, drove men insane.

Along the Palisades skyline are the ruins of a large mansion built in 1911 and demolished in the 1930s.

Series of storm drains connected to a dark urban legend.

Buildings that dynamite couldn't bring down were abandoned because of bathroom issues.

Where America's first doomsday cult awaited the end of the world.