A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

More than five miles of underground passageways.

Mile-long cave system near Great Smoky Mountains.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

Visit this playground of waterfalls, caves and sinkholes.

Railroad came. People came. Railroad left. Town died.

This structure among the trees was the result of divine inspiration.

A six-ton, 12-foot-tall concrete prairie dog is touted as the largest in the world.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

The ravine where Jesse James supposedly performed an impossible jump to evade capture.

A cemetery housing wild west legends in South Dakota.

Despite repeated attempts to make it work, this former mining town is now nothing but dust and memories.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

A waterfall 600 ft. inside a mountain, once the bane of gold miners, is now a spectacle of nature.

This psychedelic tromp l'oeil seems to be beckoning drivers to crash into a wall.

Amazing pre-Civil War ruins alongside a shallow, rocky river that hosts beautiful (but endangered) lilies.

Oldest unrestored plantation house in America that is open to the public.

"Not too many people can say they've had a nuclear bomb dropped on them, not too many would want to." — Walter Gregg.

Settled in 1696, abandoned after the Revolutionary War.

The largest wooden building in the world now houses a fascinating collection of aircraft.

The first North American landing spot for James Cook on his third voyage of discovery in the Pacific.

Mountain known by the Tillamook Tribe as "the place of the supreme deity."

Despite a legend that says this highest peak in Oregon was climbed in high heels scores of people have died on its slopes.

1920's mining camp and environmental education center is serving to protect the surrounding forest, one of the last of its kind in the Pacific Northwest.