This bug-eyed water wheel uses the power of the Sun to clean up Baltimore Harbor.

A dedication plaque on this Boston tunnel is a microcosm of a massive, controversy-laden construction project.

This preserved wilderness hides the remains of a colonial grain mill used to feed George Washington's troops.

The rare American Civil War-era weapon was never fired in anger.

Brooklyn's Barkaloo Cemetery is the resting place of a scant two bodies.

A curious friendship between two inanimate ladies.

The mass grave of a heroic Revolutionary War regiment sits below an empty lot near the Gowanus Canal.

The façade of this building looks like a bingo board, but it's really a giant clock by a famed graphic designer.

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

Magnificent New Deal Murals evoke a time when New York City harbor was one of the world's greatest and busiest ports.

On the Hudson resides one of the largest clocks in the world.

This evocative New Jersey statue memoralizes the Polish victims of a Soviet massacre.

Hidden in plain sight on the Hudson River is an abandoned train station where nature has taken over.

World Trade Center memorial likened to a woman's sexual organ.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

Three and a half miles of cliffs, rocky beaches, Gilded Age mansions and 40 Steps to nowhere in particular.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

"A hideous albatross in the Hudson River Valley."

Experience the hysteria of a 17th century witch hunt through goofy reenactments and wax dummies that should probably be burned at the stake.

The 340-year-old house that inspired the classic Nathaniel Hawthorne novel.

Statue in Salem of the woman who starred as the witch Samantha in the sitcom "Bewitched."

"the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well . . . The pure Walden water is mingled with the sacred water of the Ganges."

Louisa May Alcott based “Little Women” on her experiences growing up in this house with her sisters.

The glowing blue Nymphaeum of Emperor Tiberius.