The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

When ecosystems collide in the arid Southwest.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

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

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.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

Long before guestbooks and hotels, frontier travelers signed their names on this rock face.

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

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

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

The world's largest Holstein cow.

A true roadside icon standing on the same plains that the herds once roamed.

This long unused shot tower on the Mississippi remains a point of pride for a small city in Iowa.

A pop-culture attraction outside of Dyersville, Iowa, hits a home run.

An obelisk commemorating Lincoln's role in connecting the coasts.

This family driveway also serves as the highest point in Illinois.

This national park on the shore of Lake Michigan features remarkable dunes that lie at the heart of a Chippewa legend.

This scenic overlook commemorates the tragic death of a soon-to-be-married lumberjack.

A popular place to pick up prehistoric coral fossils from the time when Michigan was an ocean.