More than 12,000 years ago, this park was a playground for mastodons.

A natural sandstone bridge nestled within a mature forest in southern Illinois.

Another in a long tradition of legends regarding infernal seats.

One of America's first planned communities is preserved in a state park.

First crafted during the 19th century, the mill was fully restored in 1983.

If there's another drive-through golf-cart bar in a bat-filled cave on top of a mountain, we don't know about it.

Some of the oldest exposed rock formations in the United States.

The largest riverfront opening cave in the Ozarks.

A historic, scenic mill that was forced to close due to overlogging.

One of the deepest springs in Missouri.

Around 50 million gallons of water flow from this spring every day.

Erosion and time have created a naturally-formed water park.