A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

It is still illegal to "quarrel" at this unlikely urban oasis built on top of an electrical substation.

On October 17, 1814, a 15-ft. wave of beer ran rampant through the streets of London.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

A collection dedicated to the treatment of disease, held in London's oldest hospital.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

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

One of the last Jazz Age "Wonder Theaters" in New York City.

A popular European tradition makes its way to the states on one of America's most famous bridges.

One of the last few places in Manhattan that employed a pneumatic systemic keeps it on display.

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

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

Great place to have a drink and a bite to eat in an atmosphere laden with New York's Bohemian past.

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.

The oldest operating apothecary in the US has treated everyone from Thomas Edison to Mark Twain.

Tucked away amidst some of the most famous addresses in the world is New York's only fraction of a street.

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

Peek through the gates at this oasis from the city, full of Old English charm.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

A celebration of capitalism in Midtown.

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

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

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