This shallow pit was once used to send over 20,000 buffalo plummeting to their death.

The crumbling structure is a rare surviving relic of the area's bygone mining industry.

An antique Beechcraft airplane serves as a giant windsock for people driving through the blustery open country of eastern Wyoming.

The first declared National Monument in the United States.

The final resting place of the living embodiment of the famous Forest Service symbol.

This is one really big nut.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

An incredible airplane graveyard sits outside this small museum dedicated to preserving aviation history.

A monument to the one-armed geologist who led the first documented expeditions through the Grand Canyon.

This golf ball–shaped former desert real estate office now houses a UFO museum.

A self-built castle made by a mysterious man.

A museum and tribute to a brave profession.

This striking public art installation is suspended above a public park, designed to gently move in the breeze.

A stone pillar marking the location of the westernmost battle of the American Civil War only honors one side of the conflict.

What is the Thing?

This Texas windmill field celebrates the power and majesty of the very winds that blow.

A wacky, UFO-shaped house in a suburban neighborhood.

A tribute to the little-known group of women who were the first ever to fly aircraft in the U.S. military.

Where Santa Claus held up a Texas bank and started a statewide manhunt.

Home of the International Space Hall of Fame.

A cave's rare beauty held a cavernous secret hidden underground.

The symbol was surreptitiously built into the river bank by German prisoners of war.

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

A museum dedicated to the alleged Roswell Incident.