Two monstrous warehouses. One now holds priceless works of art, the other stands abandoned and dilapidated.

Once thought to be the fabled Holy Grail, it is now known to be an oil lamp.

Spike Lee's provocative film is officially honored right where it was made, the first time a work of art was used as a secondary street name.

A collaborative art project that transformed a neighborhood in NYC's Queens.

A monument stands to the famous suffragist who penned the declaration for women's equal rights, including the right to vote.

This nostalgic blast from the grooming past is also a working barbershop.

The only surviving sidewalk clock in Brooklyn.

Where infamous mobster and leader of Murder Inc. Albert Anastasia made his home.

The only remaining building in New York to see the inauguration of a president is being slowly overtaken by a grocery store.

A working monastery hidden away in Brooklyn once abutted the location of a former inebriate's home.

This Upper East Side apartment co-op was designed as a tuberculosis sanitarium.

A memorial to the first person killed by a motor vehicle in the Western Hemisphere.

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

On this island, you suck away your garbage via an elaborate pneumatic tube system.

One of the last taxidermists in New York City.

2,000 barrels of aging beer hidden in a warehouse at the Brooklyn Navy Yard.

A well-worn marker in a forgotten alleyway is all that remains of what had been one of Manhattan's most beautiful buildings.

This neo-Gothic former auto showroom is one of the few remaining reminders of Brooklyn's "Automobile Row."

Walking around West Harlem reveals a scavenger hunt of beautiful bird murals.

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

A Collegiate Gothic quadrangle that surrounds an 18th century secondary school whose financing came from the likes of Alexander Hamilton and Aaron Burr, among others.

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

These ornate manhole covers were used for a now-forgotten purpose.

The oldest Methodist church in the United States has been spreading the good news for over two centuries.