This London plaque marks the spot where David Bowie's famous alien made his debut.

A student driver's nightmare.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

A kaleidoscopic warehouse-maze of handmade neon signs.

A hot dog stand where the heads are just as hot as the dogs.

Nonprofit art center that promotes outsider, intuitive, and self-taught art.

An abandoned Roman salami factory has found new life as an art space home to 200 squatters.

Hidden behind a gate in Greenwich Village is a little farmhouse that once served as the writing studio of a bestselling author.

This narrow shop in the East Village hosts a matchmaking service for the new millennium.

The artist and New York City icon lived, worked and died in this converted carriage house owned by another iconic artist, Andy Warhol.

An extensive collection of fine art devoted to man's best friend.

The first museum in the United States dedicated entirely to posters.

The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

Elevated freight railway turned wildly successful urban park.

A New York garbage depot holds a secret collection of weird and wonderful refuse.

Every animal in the torah taxidermied and crammed into a Brooklyn townhouse.

This interactive gallery makes you feel like you've stepped into a fantasy world filled with whimsical monsters.

“Invented in Key West, Perfected in Brooklyn."

One of New York's best collections of pinball is hidden in a secret bar in the back of this laundromat.

Sniff the Titan Arum's rotting flesh.

A unique music museum housed in a historic Boston theater.

A men’s restroom became a sandwich shop.

Narrowest house in Boston.