A 35-foot-tall fork stuck in the ground outside an office building in Missouri.

Like Stonehenge, but with boats and oodles more charm.

The maximum security facility was once thought to have "the bloodiest 47 acres in America."

A mysterious light of unknown origin on the backroads of Missouri.

A geological oddity formed by two rivers carving out a mass of limestone on both sides.

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

A creepy sculpture of a decapitated head invites viewers to see St. Louis through its empty eyes.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.

Curious cave that stays a cool 56 degrees all year long.

This Great Plains museum pays tribute to both the prosperity and tragedy of the North American fur trade.

A fascinating collection of art made from petrified wood and fossils by two octogenarian twin brothers.

Other-worldly rock formations and ancient fossils abound in this unique stretch of Nebraska badlands.

This erect, phallic geological spire wasn't always named so domestically.

Remnants of a quarry company town still stand on the banks of the Wapsipinicon River.

Largest gathering of hobos in the country has been meeting annually since 1900.

The highest point in Iowa, while not that impressive to mountain states, has earned its own monuments.

Most comprehensive museum in America devoted to one ethnic group.

The oldest university museum west of the Mississippi retains its 19th century feel.

The notorious couple camped at this site after a bloody shootout with police.

An eclectic assortment of medieval architecture in a small Iowa town.

The world's only three-story rotary jail is now a museum to a bizarre trend in prison design.