A Mars simulation in the southern Utah desert.

Dramatic river bend surrounds a natural red-rocked pedestal.

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

This quiet park's strange sedimentary spires were named after Kodak's color film.

Centuries of crashing waves carved out this small hole in the rock, which lights up at certain parts of the year.

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.

The unusual patterns in this rock formation result from two distinct modes of weathering.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

This stretch of beach along California's central coast is a busy highway for the largest seal in the northern hemisphere.

A remote crossroads honoring a fallen talent.

One of the largest trees of its kind in California.

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

The site of Billy the Kid’s most famous escape and the end to the Lincoln County War.

Along a California highway is a kind of Jurassic Park made of metal.

Limestone caves with spectacular showcase chambers.

A statue honoring 44 continuous years of greeting passing ships.

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

This bare tree might not have leaves but it is constantly clothed in festive decorations left by mysterious local benefactors.

One of the tallest waterfalls in Africa is also home to a population of monkeys who enjoy the waters and the occasional guest.

Thousands of narrow alleyways in an ancient medieval city make up what's believed to be the world's largest car-free urban zone.

Europe's oldest still-operational tea farm also boasts a spectacular view.

Abandoned Coast Artillery fort now serves as graffiti canvas and sightseeing vantage point.

The place where Samuel "Slater the Traitor" brought the Industrial Revolution to America.

This alley in downtown Chicago held the bodies of over 600 people after the fateful Iroquois Theatre fire.