Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

Sitting in the arguable birthplace of the Wild West, this museum holds the largest collection of bronco busting bric-a-brac in the world.

Infamous marsh filled with toxic waste, World War II-era London rubble, and dead mobsters galore.

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

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

Currently housing a corporate bank branch this building at the southern tip of Manhattan was once the gateway to luxury vacationing.

The land is home to swimming ponies and a legendary 18th-century treasure.

The mysterious canine hides atop a drain pipe on the back of the building, some say as a sneaky shoutout to Yale.

The ruins of this Thomas-Jefferson-designed mansion have been left to crumble since the Christmas Day they burnt down.

World War II bunker still standing on the New Jersey beach.

WWII-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers. .

A grotesque Fiji merman dwells within this traditional Dutch-style building.

The historic home still shows the scars from a little run-in with the British in 1813.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

An Irish Memorial commemorating those who perished due to potato blight.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

The first American department store, and home to the largest operating musical instrument in the world.

World's first "penitentiary," meant to be humane, drove men insane.

Yo, Adrian!

Golden and naked, the figure that was once the highest point in New York is all that remains of the second Madison Square Garden.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

The oldest farmer's market in America is so ancient it was approved by the King of England.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

Berkeley Hot Springs presents to you "the only outdoor monument to presidential bathing."