ON A SUNDAY AFTERNOON in early autumn, Adam Teller pulls up in a mud-slathered blue Wrangler and steps out into a windy motel parking lot in Chinle, Arizona, yakking quietly on his cell phone. A rail-thin Navajo in his mid-forties, he has a standard-issue ponytail, with a few nuggets of turquoise accenting his fine-boned frame, but something about him says right off the bat, "21st-century Indian."

Adam removes his shades and waves at me. There's that moment of tentative recognition all guides must have with their clients: Whoever this joker is, I'm stuck with him now.

I walk over to Adam, and find that I instantly like him. "You surprised by the way I look?" he says, shutting off his phone. "A lot of people say, ‘Why aren't you in your buckskins?' They seem real disappointed. They think I ought to be making arrowheads or something." He chuckles. "Or living in a fucking tepee!"

Oafish bilagaana that I am, I shake Adam's hand, but he gives me the customary limp-fish grip that Anglos find so unsatisfying. Then he flashes a warm smile of dental calamity, his teeth twisted, banged up, or missing in action. "Used to be a motocross biker," he says. "Broke my ankle, broke my hip—man, those were the days."

I'm not the sort of traveler who ordinarily seeks out a guide, but at Canyon de Chelly National Monument, in the wrinkled recesses of northeastern Arizona's Defiance Plateau, I have no choice. Although the National Park Service runs the place, and has done so since the monument was created back in 1931, the park is set entirely on Navajo reservation land. And so, by federal and tribal law, a visitor can enter the canyon only when accompanied by a licensed Navajo "interpreter." The partnership here is unusual, and sometimes strained—and in fact many tribespeople want the Navajo Nation to reestablish complete control of the canyon.

But the guide requirement is a good idea, all in all. It's a way to protect the sacred sites and the many Navajo who still farm in the canyon from dumbass, potsherd-stealing tourists—while ensuring that local Navajo like Adam Teller have a livelihood. Since the Navajo Nation has steered clear of casinos, this sort of enlightened tourism provides one of the few sources of income around Chinle, a dreary outpost of double-wides, snarling rez dogs, and an unemployment rate four times greater than in the rest of Arizona.

Adam is, by all accounts, one of the best guides around. He started leading tours in Canyon de Chelly when he was a gangly kid of 13—he was the youngest certified Navajo guide ever. Taking people through the canyon is something he's always wanted to do—and he still has that wide-eyed eagerness of a boy keen on showing you his tree house.