Home to the deepest rift anywhere on Earth.

A tiny red pebble marks what may be the quietest outdoor spot in the United States.

Rustic natural hot springs in the deciduous rain forest.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

A library of only unpublished manuscripts.

Forever immortalized in concrete, this Simpsons etching was crafted by show creator Matt Groening.

This collection of neon icons is preserving Arizona's history, one sign at a time.

A nature and cultural preserve named for its multitude of petroglyphs carved by the Northern Sinagua people.

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

Colorful Native American paintings are hidden within this small cavern.

Eons ago, a rushing lava river formed this pristine passage through solid rock.

Bootleggers ran booze beneath this building before (and after) Route 66 appeared beside it.

The eroded core of an ancient volcano is now accessible by a short hike.

One of the world's largest telescopes, stares into the night sky with two huge mirrors.

The largest copper mine in Arizona, this enormous open pit emerges from the hills like an alien landscape.

An homage to everyone's favorite prehistoric cartoon family.

The Magical World of George Phar Legler.

A scenic ravine with an astounding collection of rock art created by the Indigenous people of the Great Plains.

This spectacular track has run continuously since 1882.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

One of the American Southwest's most extensive collections of Navajo rock art.

A working cattle ranch with remarkably well-preserved prehistoric petroglyphs and ancient ruins.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.