This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

This collection of Wild West movie memorabilia also claims to hold some secrets of the Lost Dutchman's mine.

Some of the tallest ancient American ruins continue to inspire awe and curiosity.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

Limestone caves with spectacular showcase chambers.

The world's longest known cave system.

A stone face watches over the river.

The titular fictional logger only inhabits this otherwise historically focussed museum via a piece of fiberglass kitsch.

The largest dune field in the Mojave offers a chance of hearing the 'singing sands.'

Decommissioned experimental solar facilities that pioneered solar energy technology.

Where NASA's satellites and rovers phone home.

This giant temperature attraction created some giant electric bills.

A former utopian healing center created by a huckster and built by derelicts.

The Battle of Atlanta in 360 degrees, featuring a corpse that bears a striking resemblance to Clark Gable.

Designed by Maya Lin, the memorial honors 41 individuals who died fighting for equal rights between 1954 and 1968.

A 56-foot tall statue of the god of fire looks out over Birmingham, Alabama.

148 feet long and in the middle of a verdant forest.

Once one of the largest producers of pig iron in the world.

A miniature city built by a single hunchbacked monk.

Bizarre living fossil only grows in a small chunk of the Namib Desert.

Fossils, railroads, and waterfalls!

Every fall this lake mysteriously drains, like a bathtub with the plug pulled out.

A surviving remnant of the thick ice mass that once mantled most of Western Canada's mountains.

The private clubhouse for the members of the Academy of Magical Arts.