This blowhole is supposedly caused by a trapped monster.

Submerged lava formations create incredible waterworks.

The world's largest otter started his life as a high school shop project.

This soaring sculpture and Sioux Falls landmark represents the leap of faith taken to make one's dreams come true.

More than 7,000 gallons of water pour over these cascading red quartzite waterfalls every second.

Profile of a sleeping person four kilometers long in 250-meter-high cliffs.

Half of a waterfall goes into the river while the other half seems to disappear.

This picturesque cliffside beacon no longer calls to sailors but shines once a year in honor of a famous shipwreck.

An amazing collection of sculptures and art.

Ever wanted to can Spam?

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

A museum dedicated to the alleged Roswell Incident.

A fitting attraction for the corn capital of the world.

A six-ton, 12-foot-tall concrete prairie dog is touted as the largest in the world.

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

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

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

The oldest extant wooden jail in South Dakota and possibly the United States. 

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

An experimental, automotive replica of Stonehenge.

Built in 1981 in collaboration with Andy Warhol, this giant piece of pop art stands on the campus of Colorado State University.

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

This volcano rises like a giant anthill from the plains below, with a road spiraling up to the rim.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.