The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

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

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

New York's oldest magic store.

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

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

A psychedelic labyrinth on the San Francisco bay.

This shop and studio is dedicated to the art of the book, from letterpress to bookbinding.

An artsy hidden staircase leads to breathtaking views of San Francisco.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

A modern mechanical planetary system, part of a 10,000 year clock.

This neighborhood grocery houses a treasure trove of Eastern European delights.

A man killed in a hunting accident is eternally guarded by a granite hound tombstone.

A collection of haunted artifacts chronicles the career of the world's most famous paranormal investigators.

A former connection to City Island, it has been abandoned since the 1930s.

A once crucial portion of the Long Island railroad still lays abandoned, waiting to be turned into an urban park.

This hidden library of physiological ephemera contains centuries worth of knowledge on the vim and viscera of the human body.

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

This Russian bar-restaurant lies within a three-story underground bathhouse.

Red frames showcase remnants of one of New York's original subway stations.

Cheap pizza and all of your naughty bedroom needs housed in a stunning example of Art Nouveau architecture.

A bit of retro transportation flair preserved in the world's largest department store.

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

Unique antiquarian shop specializing in globes, maps, and prints.