Two geoglyphs that are truly unique to North America.

A colorful, century-old cemetery of the Yaqui Indian Tribe hidden amid the suburban sprawl of Tempe, Arizona.

When it was built in 1929, this historic bridge was the only place to cross the Colorado River for 600 miles.

Some 10,000 works of ancient rock art cover these volcanic basalt outcrops near the Gila River.

These elusive, isolated rodents evolved into a distinct, locally iconic subspecies.

An off-the-beaten path cave with an underground lake.

Hike the unusual hoodoos and rock formations that form this little-known natural wonder.

A partial tunnel blasted into a steep ridge is all that remains of a failed railway across Arizona.

Walk through the actual strap iron cells and solitary chambers of Arizona Territory’s first prison.

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

Limestone caves with spectacular showcase chambers.

Thousands of Mexican Free-Tailed Bats soar around an abandoned storm drain at sunset each summer.

America's only nuclear missile silo open to the public.

This historic national park is covered in the stunning ruins of red rock pueblos.

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

Ancestral Puebloan ruins, natural arches, and box canyons abound in this seldom-visited corner of Monument Valley Navajo Tribal Park.

An abandoned facility that has become a place of ritualistic satanic worship, or so rumor has it.

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

Rippling sand dunes frozen in the Arizona rock.

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

In a 345-million-year-old cave that's 200 feet underground, dinner awaits.