A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

This diesel train serviced the Brooklyn waterfront for more than three decades.

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

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

Hear the tales of New York's most notorious criminals.

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

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

While it now takes more than a dime to open an account this historic Brooklyn bank still displays the opulence of the gilded age in which it was built.

Empty, but not abandoned, this cavernous Brooklyn loading dock was once considered the largest individual building in the world.

An abandoned subway tunnel that could have reinvigorated Staten Island still lies somewhere beneath this Brooklyn park.

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

An oasis of calm amid the chaos of the boardwalk, the museum traces the heritage of this beloved beachside amusement park.

An abandoned tuberculosis hospital said to be haunted by the patients who died within its walls.

A small but charming botanical garden that contains many exotic plant species.

Lavish royal estate punctuated with heated greenhouses.

The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.

This small group of sand dunes manages to pack in a strange rainbow of colors.

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

Ride the rails on a train harkening back to a 19th-century marvel.

An exquisite Baroque church in Vienna's old town.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Visiting this café is like visiting the Austrian grandma you wish you had.

A rooftop restaurant hides in plain sight atop Vienna's Palace of Justice.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.