When you drive in to Monument Valley, you half expect to be greeted by a cowboy. So closely tied to the image of the Wild West is this spectacular realm of soaring sandstone monoliths that you can practically hear John Wayne's voice drawling in your ear. Several of the Duke's most celebrated movies were filmed here and his heavy footsteps seem to echo across the dusty ground.
But today my guide is a man who might be described as the cowboy's traditional rival. To be more specific, Dennis Tsosie is a Navajo, a son of the forefathers who carved out survival in this barren landscape centuries before the arrival of interlopers in large hats and jangling spurs. And fittingly, he is clad in local dress appropriate to both the season and the location: jeans, trainers, gloves, a thick padded jacket. It's winter, and Monument Valley is desperately cold, its fabled orange terrain lightly dusted with frost.
He's waiting for me outside Goulding's Lodge, the main accommodation option in this geological wonderland. Less than a mile away, the Utah-Arizona border slices straight through the Valley. But any thought of the heat haze and oppressive sun often associated with these desert-tinged states is quickly dispelled by a sharp gust of wind. Tsosie puffs out his cheeks and rubs his hands. It is time to move.
As we clamber into the car, I ask how long he has lived in the Valley. "Born here, raised here, still here," he answers gruffly – but not without a flicker of a smile.
For all the area's screen heritage as a place of saddles and stirrups, this is firmly Navajo land, bounded into one state-line-straddling enclave as the Monument Valley Navajo Tribal Park. Tsosie points out a hogan – a squat dwelling of the type former generations would have lived in. Built of cedar and juniper, with mud compacted on to these sturdy logs for insulation, it talks of a simple existence, a smoke-hole cut into the roof for ventilation. It speaks, too, of hard labour. A glance at this world of rock demonstrates that wood has always had to be sourced from elsewhere.
Outside, Tsosie prods at the icy earth with his foot. "We have snow here, yes," he says. "But this year, very little." He shakes his head. "That means we're in for a dry summer."
He may consider the frost a wan offering, but this daubing of white gives the formations of Monument Valley added glory. Their temporary paleness is a reminder that everything here was created by glacial erosion: the twin up‑thrust thumbs of Left and Right Mitten; the ancient bulk of Sentinel Mesa and Merrick Butte; the high-rise cox-comb of Big Indian and the rough-hewn spire of Totem Pole; the epic cavern of Big Hogan, which manages – a vast circular gap in its dome – to echo both the low-slung Navajo house and the graceful majesty of the Pantheon in Rome.
At one point we look out across a wide vista. Tsosie asks me what catches my eye. I pick out a few of the shapes on the ragged horizon, with its giant bluffs and stark angles. I ask him in return what he can see. "Home," he grins.
Goulding's Lodge, Monument Valley (001 435 727 3231; gouldings.com). Doubles from $78 (£49), room only. Valley tours, with Navajo guides, from $55 (£34).