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

The hotel where Martin Luther King Jr. was shot is now a museum dedicated to his work.

Mile-long cave system near Great Smoky Mountains.

This head-spinningly bizarre Depression-era art cave is wall-to-wall quartz and Jesus.

The secret city built by the Manhattan Project.

More than five miles of underground passageways.

Visit this playground of waterfalls, caves and sinkholes.

Better known as the "Body Farm," this unique research facility has been studying how human bodies break down since the 1980s.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

All that's left of the quintessential "cabin in the woods."

Home of an evil witch famous within southern folklore.

Enormous lake at the bottom of a unique cave system.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

A museum, walk-through diorama, and library nestled under one castle-like roof.

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

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

The oldest extant wooden jail in South Dakota and possibly the United States. 

This vintage train once gave new meaning to “swimming upstream.”

A relic of roadside lore and perhaps the first of its kind in North America.

More than 7,000 gallons of water pour over these cascading red quartzite waterfalls every second.

An impressive collection of farm equipment and other artifacts from life on the prairie.

The cliff and rock formations are made out of Sioux Quartzite.

Dedicated to the history of the 1,000 nuclear missiles that once covered the Great Plains.