Cryptic messages embedded in the New York City sidewalk.

A psychological self-portrait in the form of a giant, segmented head.

"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."

Formerly the world's largest, this Willy Wonka-esque contraption runs 24/7.

The state's oldest continuously operating museum houses more than 5,000 Civil War artifacts.

This Nevada lake holds its titular natural pyramid and, if the legends are true, a number of dangerous spirits.

A discreet little stairway on St. Nicholas Avenue leads to a quaint and unexpected cobblestone street of 19th century wooden rowhouses.

The site of a tragic massacre that spawned a multimedia franchise.

This lone tree and dramatic sandstone outcropping are so beloved by Michiganders they can be found on one of the state’s coins.

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

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

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

The interior of the Overlook Hotel in "The Shining" was based on this Yosemite original.

The U.S. Supreme Court's secret Cold War relocation facility in the mountains of North Carolina.

Watch the newest land on the planet form before your eyes.

Massive still life just off the highway in Kansas.

The rough and tumble president's childhood home displays the shirt he was once shot in and the speech that saved him.

Plot your trip through the city on the sidewalk.

Charleston's historic city jail once held everyone from pirates to Civil War POWs.

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

The lighthouse central to the 1980s horror classic "The Fog" is, in fact, located in one of the foggiest areas of the Pacific Coast.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

Eclectic collections, artwork, and some feline friends fill the writer's former home.

Hidden behind Lincoln's head is a chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.