Scattered throughout London are ancient remnants of the city's former bounding wall.

London's smallest police station is barely the size of a phone booth.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

Stunningly detailed mosaics in a New York subway station bring life to the Weimaraners of artist William Wegman's work—and to thousands of commutes.

This 19th-century Hamptons windmill was once home to modernist painter Agnes Pelton.

This magnificent herd of stampeding elephants has been frozen in time for over a century.

Here be dragons.

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

The real-life site of Ichabod Crane's infamous gourd attack.

The former sign of this immortal music venue is just that--undying.

Those belting out show tunes might not realize this piano bar marks the site where Thomas Paine died in 1809.

The first piece of public art dedicated to LGBT rights.

This New York holdover was built to provide housing for shopgirls and still does not allow men above the lobby.

A sewing machine tycoon built this miniature castle for the people and to beautify a lakeshore.

Beautiful mosaics cover the first stations opened on New York City's newest subway line.

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

A whimsical, but often overlooked clock in Park Avenue.

The name of this tiny pocket park tucked between two buildings on Manhattan's Upper West Side is Latin for its location: "seventy-one."

America's greatest forgotten garden and the former stomping grounds of Son of Sam.

Plot your trip through the city on the sidewalk.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Love, knishes, and best wishes from this legendary Lower East Side bakery.

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.