This study room in the New York Public Library saw the creation of one of contemporary America's greatest traitors.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

A whimsical, but often overlooked clock in Park Avenue.

A 19th-century politician who died after walking home in a blizzard is honored with this Manhattan statue.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Cryptic messages embedded in the New York City sidewalk.

Elevated freight railway turned wildly successful urban park.

A reminder to choose water over wine since 1888.

One of the few remaining American elm trees in New York’s Tompkins Square Park was the birthplace of a new religion.

This exemplar of modernist architecture is meant to captivate and inspire students of the Cooper Union.

New York City's smallest piece of private property.

Plot your trip through the city on the sidewalk.

Try not to get slimed in Tribeca.

Avoid gangster interaction while window-shopping.

During the 19th century, you could pay for violence off a prix fixe menu on this Manhattan street.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

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.

The façade of this building looks like a bingo board, but it's really a giant clock by a famed graphic designer.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

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

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

Unrepaired walls from a 1920 anarchist bomb attack.

Possible relics of the ancient Roman city are hidden in this restaurant's façade.