An acoustic anomaly with a mysterious cause.

The remains of a foundry and old blast furnaces destroyed during the Civil War are preserved in this central Alabama park.

Over a dozen Native American earth mounds dating back over 2,000 years dot this Tennessee archaeological park.

These ruins are all that's left of the former Alabama State Capitol.

This university research project is the U.S. government's weed dealer.

Constructed from bricks salvaged from a former dormitory destroyed in a fire.

This architectural triumph is the only Frank Lloyd Wright house in Alabama.

A 50-foot-tall replica of the infamous lamp from 'A Christmas Story' illuminates this small town.

Is this 47.7-mile stretch of highway the longest straight road in the United States?

A half-size replica of the World Trade Center towers above Tulsa.

Behind the Cowboy Hall of Fame is a burial ground for good horses and a famed rodeo bull.

Songwriter Leon Russell transformed this church into a recording studio used by many legendary musicians.

The surprising home of the iconic Santa Monica Pier Ferris Wheel.

A detached cement mixer has been transformed to resemble a relic from some obscure NASA mission to Oklahoma.

This historic theater's pipe organ still accompanies silent films just like it did in 1929.

This abandoned, windowless concrete block is one of the strangest buildings in Tulsa.

Nature's biggest mammal swims in landlocked Oklahoma.

This tiny, triangular block has held the world record since 1964.

Dothan, Alabama has been invaded by scores of anthropomorphic peanuts.

You'll need cowboy boots to trek to this old-fashioned saloon nestled in a giant natural cave.

This Mississippi seminary was the first in America to train Black Catholic priests.

In the mid-20th century, a tamale-slinging juke joint attracted a diverse clientele in the Mississippi Delta.

People of the Plum Bayou culture built these enormous mounds over 1,000 years ago.

Two gushing waterfalls of hot spring water within a block of each other.