This tiny patch of arid sand sits in one of the greenest states in the United States.

This grave marks the final resting place of a legendary frontiersman... unless it doesn't.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

The show pony of cave systems, Fantastic Caverns manages to live up to its name.

European castle ruins in an American state park are actually the product of death and grief.

It's big, it's a ball, and it's made of twine—the world's largest of its kind.

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.

This abandoned prison castle has become an imposing gallery of graffiti art.

Four, 18-foot-tall badminton shuttlecocks lie scattered about the lawn of a Kansas City museum.

This Italianate Villa-style castle is pretty to look at, just keep off the private property.

Marking the spot where a conquistador gave up his search for the fabled Seven Cities of Gold.

Ancient pueblos built into the base of a natural canyon wall.

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

See massive fossils that are over 200 million years old in northeastern Arizona.

A starship has landed in Texas, a welcome break for weary travelers from a drab stretch of I-35.

Crumbling hotel echoes with the sounds of the '30s.

Tracks near this Texas nature site were once thought to support the Creationist belief that man and dino coexisted.

This grimly-titled Texas cemetery is all that remains of a Wild West settlement with possibly the worst name.

Mysterious glowing orbs float through the desert night.

A spring-fed pool so deep it's used for scuba diving as well as swimming.

A recreated Stonehenge stands in a country field, complete with Easter Island moai heads standing as sentries.

Free public park and gardens filled with peacocks and peahens.

An enormous pink granite batholith, long attributed with spiritual powers by the Tonkawa Indians.

Modern technology and live displays tell the story of the Pacific during WWII for the Internet generation.