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

The studio of influential composer Charles Ives is perfectly reconstructed, hidden in the back of the American Academy of Arts and Letters.

Depression-era fun lives on in this Harlem museum dedicated to the sport of the street.

These small stands sell Malian snacks to worshippers and passersby after Friday prayers in Harlem.

Gang fights don't just happen on the streets, they happen under them too.

The only gallery in New York dedicated to olfactory art and the exploration of scent in art.

The legendary court where emerging basketball players gain their street cred.

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.

A commemorative plaque hides a door that leads down to the New York Public Library's underground book bunker.

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

Magnificent New Deal Murals evoke a time when New York City harbor was one of the world's greatest and busiest ports.

This vacant church in the Financial District was once the heart of New York's first Syrian immigrant community.

A memorial marks the library lobby where Langston Hughes' ashes are buried.

This nearly invisible wire transforms much of the city into one big, symbolic home on the holy day.

The competition: breathe deeply as long as you can.

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

A replica of a 7th-century church hides in plain sight in the middle of the concrete jungle.

These historic buildings once housed the headquarters of one of the most infamous gangs of New York.

Manhattan's Thirteenth Avenue was made on landfill then deliberately destroyed — apart from one small, obscure block.

This 220-year-old house is a reminder of New York City's Dutch past.

The greatest real estate coup of all time.

The smallest island in Manhattan is a manmade landfill dominated by a Buddhist peace arch.

A prized globe signed by Amelia Earhart and Charles Lindbergh sits in the Brooklyn office of the American Geographical Society.

Jimi Hendrix's legendary recording studio in Greenwich Village.