An unassuming secret door once led to a legendary watering hole.

One of the last Jazz Age "Wonder Theaters" in New York City.

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

This former Norwegian sailor's church is slowly being taken over by ramshackle robot musicians.

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

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

Nondescript elevator doors open to reveal a stunning, surreal world.

Nikola Tesla's former home contains an homage hidden from plain sight.

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

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

A restaurant on Staten Island showcases a different grandmother’s cooking every night.

Ride the subways of yesteryear.

Read a book next to a Midtown waterfall.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

A hands-on traveling collection of the innovative devices of yesteryear.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

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

A miniature rainforest is growing inside of a Midtown Manhattan office building.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

Resembling a 15th century medieval fortress, this home once belonged to a legend of Mexican cinema.

This underground museum highlights the history of Mexico City's subway system.

The museum houses "the most studied meteorite in history," among other geological oddities.