NYC's legendary underground network for bovine transportation.

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

An homage to Jackie Gleason's bus-driving character from 'The Honeymooners.'

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

Amid the marketing blitz of modern Times Square is an elegant holdover from its showbiz glory days.

The 28-foot granite map plots the locations of 40 theaters in New York City.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

A very classy 1920s-era bar right in Grand Central Station.

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

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

A plaque immortalizes the spot where the early American spy said his famous last words: "I only regret that I have but one life to lose for my country."

This tiny store is your one-stop shop for all sorts of rare and wonderful buttons.

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

A simple midtown bar was once the home of a secretive and exclusive club staffed by "bunnies" under Hefner's strict rules.

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.

Though the case is scorched and the buttons half-melted, this hardy handheld gaming device can still run a game of Tetris.

There are owls with glowing eyes in Herald Square.

A legendary speakeasy bookstore returns from the brink.

Visit the site of a subway powered by nothing more than air--and lots of it.

Manhattan's deadly West Side railroad, which killed hundreds of New Yorkers, is remembered by this simple plaque.

Twenty-three trees, each paired with a basalt stone, line a street in Chelsea, continuing an urban project started by German Fluxus artist Joseph Beuys.

This historic building housed the surviving crew members of the Titanic, who were left destitute after the wreck.

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