This monument marks the beginning journey of a wounded soldier's leg that ended up almost two states away.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

A beautiful geyser under environmental threat.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

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

The oldest working bell set in North America, the bells at Old North Church sat silent for their first four years in Massachusetts.

The homestead of American patriot John Adams.

The nation's second-ever First Lady urged the founding fathers to "remember the ladies."

The only road through the heart of Glacier National Park.

The king of U.S. high points towers over every other peak on the continent.

An Alaska livestock farm devotes itself to harvesting wool from creatures that once ran with mammoths and sabertooth tigers.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

Every equinox this Maya pyramid puts on a spooky ancient light show.

The park is home to the United States's only still-operating Dutch windmill.

One of the few working locomotive roundhouses in the United States.

A sealed test tube said to hold Thomas Edison's dying breath was given to the inventor's friend and mentee, Henry Ford.

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

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

Watch the ships come in on Michigan's 210 ft. high observation deck in Sault Ste. Marie.

The palatial McDonald's that inspired Wesley Willis.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Years of archaeology, just chillin' by the water cooler.