This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

Hidden behind Lincoln's head is a 70-foot-long chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.

One of America’s oldest and spookiest hotels, thanks to the residency of ghosts, dead presidents, and Alfred Hitchcock.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

This museum started by a curious collector is now a place for believers and skeptics alike.

Visitors to this museum will uncover a whimsical collection of marbles from across time.

A Winnebago Tribe collection featuring arrowheads, artwork, and a mysterious rock carving.

This little gem of a museum is a hidden jewel filled with prehistoric treasures.

America's largest man-made forest was planted in an effort to bring back the past.

This once rural mansion now sits in the heart of the city.

When an ancient supervolcano erupted, some of Nebraska's prehistoric animals were forever preserved in ash.

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

Site of the 1879 Cheyenne Outbreak and the site where famed Sioux chief Crazy Horse met his fate.

Underneath downtown Lincoln resides a network of caves that was also the city's first brewery.

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

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

One of the oldest continually operated libraries in Kansas.

Home to fossils and other specimens from the Western Interior Seaway.

One of the stops along the fateful journey of the Donner Party.

A Jurassic artscape composed of transmission casings and other mechanical parts.

This small museum contains fossils from an era when Kansas was underwater.

Once an ancient sea, this landscape of rocky ravines is filled with the fossils of ancient marine life.

Enjoy a tour of oddities and makeshift monsters at this souvenir store with an offbeat sense of humor.

This tiny old water tower once doubled as a makeshift jail.