19th century cemetery hidden in Brooklyn's Prospect Park.

This elaborate tunnel is the first structure composed of cast concrete in the United States.

A tree that grows parallel to the ground was declared Brooklyn's "crowning curio" by the poet who saved it.

The site of a fallen tree that protected Americans from British forces during the American Revolution.

This city park was once a lookout point for George Washington’s army during the Battle of Brooklyn in 1776.

This secluded ruin was once a home for exotic plants.

This striking arch, one of the first architectural elements constructed in Prospect Park, was recently restored to its original glory.

One of the deadliest American air disasters is nearly forgotten in Brooklyn.

Sunset Park's Guatemalan community knows to head to the back of this bodega for a taste of home.

The former home of the reclusive "Weird Wendels" who dominated New York real estate a century before Donald Trump.

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

Unrepaired walls from a 1920 anarchist bomb attack.

This curved Manhattan building was built to house the opulence of John D. Rockefeller's oil empire.

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

Built hundreds of years ago this downtown iron barrier once protected a much despised king.

Currently housing a corporate bank branch this building at the southern tip of Manhattan was once the gateway to luxury vacationing.

An odd, ancient window that may have once been part of a brutal prison is embedded in the side of New York's Police Plaza.

A mysterious, abandoned building rotting on the Brooklyn waterfront.

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

This iconic tattoo shop has its own onsite museum with artifacts from the early history of modern body art.

America's oldest Eastern European synagogue provided the immigrants of crowded Lower East Side tenements a space of sanctuary.

All of the Malaysian sweets at this shop are made daily with a whole lot of love.

The competition: breathe deeply as long as you can.

A notorious punk house turned co-op.