Head north on Highway 89 out of Flagstaff, Arizona, and before long the dignified and sturdy ponderosa pines that blanket the foothills around the city give way to rockier badlands as you descend toward the Diné (Navajo) Nation and the Painted Desert, the huge swath of northern Arizona stretching from Grand Canyon National Park to Petrified Forest National Park.
As the landscape opens up, the high desert’s rolling hills and craggy ridgelines unfurl in dusty hues that beg to be Instagrammed. And that’s just what you can see from the highway. Venture down any of the region’s backroads and you’ll find forgotten canyons, massive arches, sand dunes, and ancient, unmarked ruins. There are other gems, too, many of which are hiding in plain sight just off the road, such as the series of public-art installations created and curated by Chip Thomas, a 62-year-old local physician, activist, and world-renowned public artist...