The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

A hidden bar inside an ad agency has a deliberately misleading name, so employees can stay late under pretext of paperwork.

This fairy tale-themed amusement park is now abandoned, and childhood metaphors abound.

Slyly buy a shake in the Parker Meridien lobby.

There's a piece of New York City transportation history hidden in plain sight at a Manhattan subway stop.

This Manhattan skyscraper is a reminder of the brief but glorious age of urban air taxis.

Sniff the Titan Arum's rotting flesh.

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

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

The oldest bibliophilia club in America, with exhibitions on historic books and graphic arts.

You don't have to be an ambassador to dine like one.

Read a book next to a Midtown waterfall.

Haven for steampunks.

What happens here stays here – unless it affects the whole world.

On the top floor of an upscale department store stands a lavish restaurant housed in a replica of a luxury French dining car.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

Underground vaults of a former brewery beneath Brooklyn's Crown Heights are now used to ripen cheese.

A forgotten relic from New York's bygone trolley system hides in plain sight under a bridge.

Visit the monolithic tomb of America's most famous general.

The walls are decorated with whimsical murals painted by the creator of the Madeline franchise.

A crumbling hospital from the 1850s on Roosevelt Island.

This was one of the first (and last) university-built and operated nuclear reactors.

A Jewish deli run by Yemeni Muslims in an Afro-Caribbean neighborhood is quintessential Brooklyn.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.