A simple midtown bar was once the home of a secretive and exclusive club staffed by "bunnies" under Hefner's strict rules.

This historic building housed the surviving crew members of the Titanic, who were left destitute after the wreck.

Need to book a room at the Hotel Pennsylvania? Just dial up 6-5000.

A decommissioned military complex that's now a modern industrial park.

Cheap pizza and all of your naughty bedroom needs housed in a stunning example of Art Nouveau architecture.

A museum collection honoring the long history of the FDNY is held in a disused Manhattan fire house.

This once-grand marvel of engineering is now 41 miles of scenic hiking trail.

Toxic waste disaster that founded the Superfund program.

A once crucial portion of the Long Island railroad still lays abandoned, waiting to be turned into an urban park.

This outpost of America's most popular fast-food restaurant is housed inside a palatial mansion.

A prohibition era watering hole for the police.

A winding, cliffside stretch of road overlooking the Delaware River.

The most confusing clock in New York.

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.

A posh members-only club with a literally dramatic history.

A massive forgotten storehouse from 1913 on the Brooklyn Waterfront has a spectacular view of Brooklyn.

An abandoned asylum once on the cutting edge of lobotomies may be reborn as a Christian college.

Little Red Lighthouse under the George Washington Bridge.

This mouldering abandoned mental hospital was once a center for progressive healing.

Commemorating the spot where the famous scientist fed his pigeons.

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

This former theme park in New York's Adirondack Mountains fell into ruin before being resurrected as a state-run campground

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

Touching mementoes from those who didn't make it back from World War I still hang in one of New York's oldest bars.