Ride the subways of yesteryear.

Tucked in the back of this amazing antique store is an important piece of medical history.

Walk into the 19th century without leaving Brooklyn.

New York City's smallest piece of private property.

Touching mementoes from those who didn't make it back from World War I still hang in one of New York's oldest bars.

This Wall Street bar was once a hub of revolutionary activity where Washington famously bid farewell to his troops.

A hip bar decorated with walls of golden skulls.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

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

Avoid gangster interaction while window-shopping.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

The collection of intricate sculptures includes one carved from a mammoth's tusk

This colossal ancient sculpture of the monstrous Aztec rain god has a literally stormy history.

In Coyoacán, a pair of coyotes crown a public fountain in reference to the ancient Aztec name of the borough.

Frida Kahlo's childhood home, now a museum of her life and works.

Named after a Mexican president, who once lived nearby, this park in a residential Mexico City neighborhood packs a whole lot of history into a small space.

66,000 pieces of art, donated by one of the world's richest men.

You can release a young butterfly at this beautiful indoor garden.

This stunning and ethereal mural symbolizes the beauty, unity, and diversity of humankind.

Come face to face with the ferocious visage of the serpent-headed mother goddess of the Aztecs.

The striking jade death mask of an ancient Maya king is displayed in a replica tomb in Mexico City.

This colossal ancient jaguar sculpture was used as a vessel for the hearts torn from sacrificial victims.