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

This site is home to ancient petroglyphs and pictographs dating back to 6,000 B.C.

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

The hallowed remains of a 900-year old Ancestral Pueblo great house.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

A house carved into a rock in the 1940s.

A sharp bend in a dramatic river canyon cut through red rocks.

Most-visited and most-photographed slot canyon in the American Southwest.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

A tunnel with windows, so you don't miss out on the impressive views.

Although it also features red, orange, and variegated cliffs of Navajo Sandstone, this state park is often overshadowed by its more famous neighbor.

An experimental, automotive replica of Stonehenge.

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

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

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

A striking sculpture built to honor the women of the Lakota and Dakota Nations.

A cemetery housing wild west legends in South Dakota.

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

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

The first declared National Monument in the United States.

The world's largest Holstein cow.

One man's quest to save his town with a trail of record-breaking sculptures.

This vintage theme park is peak Christmas kitsch—and it's open all summer.

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