The largest natural travertine bridge in the world is nestled in a small canyon in central Arizona.

One man has installed bathtubs into the Utah desert floor to harness the powers of a natural hot spring.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

A stoic rock cairn is all that remains to remember one of the more brutal instances of frontier treachery in American history.

Ancient pueblos built into the base of a natural canyon wall.

A replica of the flagpole that gave a frontier town its name.

Witnessing the might of this dessert-colored desert waterfall is a rare, powerful treat.

Erosion and various mineral deposits give this striking canyon its distinct color and soft appearance.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

Local lore holds that Butch Cassidy took an escape route through Red Canyon's sandstone hoodoos after an attempted murder.

Colorful sand dunes create a unique attraction in this part of Utah's red-rock country.

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

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

The damming of the Colorado River buried an iconic geologic formation before record-breaking drought brought it back.

Rippling sand dunes frozen in the Arizona rock.

Giant pinnacles in the sun-scorched lands of Southern Utah have been nicknamed "white ghosts."