In the Shawnee National Forest, amazing rock formations peer through the treeline.

Where the author wrote her beloved "Little House" books.

A floating museum that was sunk by a flood and left to rot in the tides.

A late sculptor's last project was to turn this abandoned cement factory into a castle-themed amusement park.

This spot in St. Louis, marked with a simple sign, has seen more pro baseball than just about anywhere else in the world.

An abandoned factory along the Mississippi coated by a giant mural.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

The red brick house where the father of rock 'n' roll wrote some of his classic hits.

A big museum full of little worlds.

Less a museum than a bizarre fantasy world created by artists and engineers.

This unauthorized stone mermaid was secretly carved out of public stone before being permanently preserved.

A giant bronze coil of feces is both a tribute to doggie defecation and a reminder to pick it up.

A speakeasy takes on Chicago's drinking culture.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

This morbid, delightful curiosity shop offers everything from animal bones to human teeth.

This shop for all your super spy needs hides an educational secret.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

A hidden barn-sized rendition of Grant Wood's most famous, and most parodied, painting.

A place of great reverence for Trekkies everywhere, a hero's future birthplace.

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

A mysteriously dark cemetery monument fuels stories and legends galore.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

Large Hadron Collider and the Birthplace of World Wide Web.