A partially hidden wall graffitied by spectators of the 1976 Bicentennial, recently rediscovered.

In its day this historic fort held 100 cannons pointed in almost every direction to protect New York.

Ruins of a once-prized railroad station in New York.

The notorious headquarters of a corrupt political machine.

A posh members-only club with a literally dramatic history.

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.

Visit the site of a subway powered by nothing more than air--and lots of it.

The remains of a failed subway in upstate New York is now an underground graffiti bunker.

A whimsical, but often overlooked clock in Park Avenue.

100 massive sculptures in the Hudson River Valley.

Once America's longest-manned military fort, now an abandoned hulk.

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

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

A former insane asylum despised by Nelly Bly and Charles Dickens is now fashionable apartments.

Named the fifth most beautiful building in America in 1885, this former courthouse boasts the best view in the Village.

One of the last Jazz Age "Wonder Theaters" in New York City.

Home on the Hillside, and home of the first breakfast cereal.

Spinning silently in the lobby of an Art Deco masterwork is a massive vintage model of the Earth.

The site of a tragic massacre that spawned a multimedia franchise.

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.

Leaf through over 30,000 artists' sketchbooks in what may be the world's largest collection of doodles

Cryptic messages embedded in the New York City sidewalk.

For over 80 years, Mayan ruins stood proudly in a most unlikely location.