A museum, walk-through diorama, and library nestled under one castle-like roof.

Before its closure in 2002, this South Dakota mine was the largest and deepest gold mine in Western Hemisphere.

One dedicated priest constructed this beautiful stone grotto by hand from 1926-1933.

This 19th-century religious artwork was once highly controversial—because it was donated to the church by a divorcee.

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

A relic of roadside lore and perhaps the first of its kind in North America.

One of the first intercontinental ballistic missile sites in the United States.

Calidum et Deliciose Succosum!

This Wild West attraction is alive with glitching automatons.

The deserted railroad town had a last gasp as a ghost town attraction before being abandoned for good.

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

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

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

It is the only marker for one of the most famous hate crimes in American history. There are no other memorials for him in the entire state.

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

The world's largest mineral hot springs is home to a herd of bison, a free public bath house, beautiful mineral formations, and a terrifying swinging bridge.

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

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

One man's ambition created this psychedelic log home.

This 35-foot troll in Jackson Hole, Wyoming, was made by the world’s leading recycling artist as part of a global fairytale.

Welcome to a starkly beautiful sanctuary where the buffalo roam.

Once a gas station, this flightless airplane beside the Old Dixie Highway now houses a barbershop.

This video store is a horror buff's dream.

Polish babkas, cheesecakes, and rose jelly-filled doughnuts are made fresh daily at this neighborhood stalwart.