This was one of the first (and last) university-built and operated nuclear reactors.

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

Salute the leader of the proletariat.

The first "Hall of Fame" in America was designed by legendary Gilded Age architect Stanford White for what was then the NYU uptown campus.

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

There’s a secret bunker inside the Brooklyn Bridge, but the city won’t say where.

A staggering collection of photographs depicting medical, social, and historical change.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

A hands-on traveling collection of the innovative devices of yesteryear.

Unrepaired walls from a 1920 anarchist bomb attack.

This hidden library of physiological ephemera contains centuries worth of knowledge on the vim and viscera of the human body.

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

The former hotel where Tesla invented the radio.

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

The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

Long the exclusive domain of birds and vagabonds, this little-known Central Park peninsula is open to the public once more.

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

A quiet and contemplative oasis in the middle of New York's bustle and riot.

A Manhattan courthouse hides a small but scathing memorial to Holocaust injustice.

The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

A popular European tradition makes its way to the states on one of America's most famous bridges.

Deep under Manhattan is the largest construction project in city history. So far, the project has taken the lives of 23 workers, or "a man a mile."

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