Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

A small part of lower Manhattan is actually made from a bit of England.

Love, knishes, and best wishes from this legendary Lower East Side bakery.

This monument to a veteran of the Mexican-American War is one of only two in Manhattan that serve as an actual mausoleum.

This simple Manhattan salt house is artfully shaped... well, like a giant granule of salt.

This Fifth Avenue church has long been the favored worshiping place of Broadway actors and vaudeville performers.

Manhattan's deadly West Side railroad, which killed hundreds of New Yorkers, is remembered by this simple plaque.

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

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

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

The oldest living tree in Manhattan comes shrouded in sinister legend.

A masterpiece of LGBT art has been restored in what may now be the most valuable restroom in America.

This Wall Street bar was once a hub of revolutionary activity where Washington famously bid farewell to his troops.

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

This castle-like building in Manhattan helped destigmatize cancer in the 19th century.

The artist and New York City icon lived, worked and died in this converted carriage house owned by another iconic artist, Andy Warhol.

New York's oldest and possibly grandest keeper of books.

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

A Yiddish theater turned movie house turned rock and roll landmark turned gay disco turned bank.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

A legendary speakeasy bookstore returns from the brink.

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

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