One of the largest Native American shell middens stands 30 feet tall.

This winding road of 318 curves is a must-visit for (careful) motorcycle and sports car enthusiasts.

This funicular railway rumbles along for a mile up the nearly vertical face of Chattanooga’s Lookout Mountain.

The pan man stands as a testament to the functionality of American cast iron cookware.

The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.

In memory of the 110 victims of ValuJet Flight 592 that crashed in the Everglades.

Despite being burnt down multiple times, the ruins of this South Carolina church are still standing.

The smallest post office in the United States is no bigger than a broom closet.

A community of collapsing homes more than a mile out from the Florida coast.

Located within a historic park, the beacon is the oldest standing structure in Miami.

These mysterious ruins are hidden amid this sleepy coastal city.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

These ruins are all that remain of what a Spanish barrack that likely housed a quarry overseer, masons, and stone cutters involved in the construction of the Castillo de San Marco.

One of the oldest, tallest, and most haunted lighthouses in America.

Built around 1723, this is the oldest surviving home in the U.S.'s oldest colonial city.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

The stone marker that Mason and Dixon placed at the eastern end of the famous north-south border they surveyed.

This beach-side arcade is believed to be the oldest penny arcade in America.

The birthplace of the man who patented the cotton gin and pioneered interchangeable parts.

This tree is a living witness to the beginning of the Civil Rights Movement.

The dairy farm in upstate New York where nearly half a million people gathered for three days of peace and music in 1969.

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

A tradition unlike any other, this marks the site of the annual Groundhog's Day tradition.