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.

This abandoned seaside fortress is now simply an imposing ruin being taken back by nature.

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

A discreet little stairway on St. Nicholas Avenue leads to a quaint and unexpected cobblestone street of 19th century wooden rowhouses.

Avoid gangster interaction while window-shopping.

This wall on a street corner in Lower Manhattan has been a blank canvas for a rotation of renowned artists since the 1980s.

An artist's cute bronze subway sculptures belie his violent artistic past.

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

Lie in a hammock where George Washington stood.

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

Detailed facade of a brownstone in Boerum Hill.

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

Peek through the gates at this oasis from the city, full of Old English charm.

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

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

For over 30 years the walls of this Harlem schoolyard have been a gallery of street art by "Kings and better."

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

A celebration of capitalism in Midtown.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

A tunnel once abandoned now thrives with graffiti art as an off-limits makeshift gallery.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A dilapidated dock tells the story of Titanic's missed arrival.

Elevated freight railway turned wildly successful urban park.