A tunnel once abandoned now thrives with graffiti art as an off-limits makeshift gallery.

A celebration of capitalism in Midtown.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

Ride the subways of yesteryear.

Read a book next to a Midtown waterfall.

A dilapidated dock tells the story of Titanic's missed arrival.

This little museum is built on a theater that was once a wildly elaborate speakeasy.

Try not to get slimed in Tribeca.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

A simple plaque on the facade is the only reminder that the treaty ending the American Revolution was signed inside.

A font of vintage porn on the silver screen.

Inside a former cabaret, seven floors of erotic art.

This facility has manufactured stunning tapestries for France's royalty ever since the 17th century.

During the summer months, giant teddy bears take over Paris near Les Gobelins metro station.

Claude Monet was baptized in this lavishly ornate Paris church.

A beautiful Victorian statue shows France's enduring love of the rhinoceros.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

What looks like a normal building is really a hollow facade hiding a subway vent.

The narrowest street in Paris.

Ordinary art transforms to extraordinary thanks to locals' quirky sense of humor.

This little-known relic crypt holds stolen parts of a Roman Empress.

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

An iconic and eccentric bar for "Manouche" Jazz music keeps expanding its space—and its influence.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.