At the time of its completion, it was the tallest dam in the world.

The first declared National Monument in the United States.

Native Americans built this circle of stones, which was used to predict astronomical events.

Yes, this monument is aware that it is about 20 miles away from the actual center of the United States.

Every president in history is immortalized in bronze in downtown Rapid City.

An entire city block built completely out of petrified wood.

This Wild West attraction is alive with glitching automatons.

Thanks to a loophole in property ownership, this alleyway has become a cacophonous street gallery.

One of America's first dinosaur parks gives a window into Depression-era paleontology.

A place where the laws of nature seem to have gone completely berserk... but of course haven't.

This replica stave church looks like a piece of Norway was simply plopped down in South Dakota.

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.

A roadside collection of over-sized iron creations that are a bit more macabre than most.

Just a man taking his prehistoric pet for a stroll.

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

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

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

This arts and culture cultural center explores the diverse cultural heritage of the American West.

One woman's Viking Castle on Lake Tahoe.

Bits and pieces from the ill-fated Donner Party's winter cabins.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

This Taoist temple is the oldest continuously used Chinese temple in California.

California's own majestic geyser is powered by a subterranean volcano.

This historic California cemetery holds the bodies of veterans of both the Civil War and the Donner Party.