A little lighthouse in New York City, surrounded by mysterious stories of insanity-driven construction.

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

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

One of only two commuter aerial tramways in the United States.

One of only two remaining Victorian-era greenhouses in New York.

Slyly buy a shake in the Parker Meridien lobby.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

A crumbling hospital from the 1850s on Roosevelt Island.

Nature and beauty amidst pollution and industrial wreckage.

The one-stop shop for all of your superhero (or evil arch-nemesis) needs.

HBO series' stage tucked away in a Greenpoint lot is the largest theatrical set of its kind in the United States.

Four cars from the old system were once on display, but were removed in 2014.

A huge resale shop for the cast-offs of the film & television industry.

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

A modern zoetrope on the New York City subway.

Ride the subways of yesteryear.

Elevated freight railway turned wildly successful urban park.

Red frames showcase remnants of one of New York's original subway stations.

Tucked in the back of this amazing antique store is an important piece of medical history.

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

Become a prohibition rebel.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.