A cannon designed to fire an atomic warhead.

This museum features the original car used on the Beverly Hillbillies sitcom.

This haunted hotel built on natural springs once served as a hospital for a quack doctor promising a cure for cancer.

The warmest cave in the Ozarks features two seemingly bottomless lakes.

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.

Two men built this castle on the Florida coast as an artistic “landscape sculpture.”

Twenty-year effort to raise a castle using tools and techniques from the 13th century is now abandoned in the Arkansas woods.

A key producer of charcoal iron in the early 1800s, the structure still stands today.

Hiding behind a grocery store is a spectacular cavern carved as part of an old limestone quarry.

A museum dedicated to man's boldest venture.

This former Union fort commands a fine view of downtown Cape Girardeau and the Mississippi River.

This odd stone memorial remembers a loyal dog who offended the rail barons with his speed and saved his master with his pee.

Planes, trains, and automobiles have all been sunk as attractions at this Illinois diving spot.

In the Shawnee National Forest, amazing rock formations peer through the treeline.

Thousands of unique minerals, including some of the most impressive fluorite crystals in the world.

The second oldest continuously operating bar in Louisiana.

A prime example of New Orleans' unique architecture these early 20th century homes were built to look like steamboats.

This 19th-century sugarcane plantation is one of the most well-preserved estates of its kind, including its original quarters for enslaved laborers.

All that remains of this small town is its mass grave and a myth of a voodoo priestess who predicted its demise.

World's largest precision optical instrument used to detect Einstein's elusive gravity waves.

The last intact steam engine factory in the United States.

This historic general store still operates much as it did in the late 1800s.

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

A collection of huge Pre-Colombian structures in Alabama.