To live with ghosts requires solitude.

　　—ANNE MICHAELS, Fugitive PiecesFOR DAYS, I’d been searching Mexico’s Sierra Madre for the phantom known as Caballo Blanco—the White Horse. I’d finally arrived at the end of the trail, in the last place I expected to find him—not deep in the wilderness he was said to haunt, but in the dim lobby of an old hotel on the edgeof a dusty desert town.!

　　“Sí, El Caballo está,” the desk clerk said, nodding. Yes, the Horse is here.

　　“For real?” After hearing that I’d just missed him so many times, in so many bizarre locations, I’dbegun to suspect that Caballo Blanco was nothing more than a fairy tale, a local Loch Ness monstruodreamed up to spook the kids and fool gullible gringos.

　　“He’s always back by five,” the clerk added. “It’s like a ritual.”

　　I didn’t know whether to hug her in relief or high-five her in triumph. I checked my watch. Thatmeant I’d actually lay eyes on the ghost in less than … hang on.

　　“But it’s already after six.”

　　The clerk shrugged. “Maybe he’s gone away.”

　　I sagged into an ancient sofa. I was filthy, famished, and defeated. I was exhausted, and so weremy leads.

　　Some said Caballo Blanco was a fugitive; others heard he was a boxer who’d run off to punishhimself after beating a man to death in the ring. No one knew his name, or age, or where he wasfrom. He was like some Old West gunslinger whose only traces were tall tales and a whiff ofcigarillo smoke. Descriptions and sightings were all over the map; villagers who lived impossibledistances apart swore they’d seen him traveling on foot on the same day and described him on ascale that swung wildly from “funny and simpático” to “freaky and gigantic.”

　　But in all versions of the Caballo Blanco legend, certain basic details were always the same: He’dcome to Mexico years ago and trekked deep into the wild, impenetrable Barrancas del Cobre—theCopper Canyons—to live among the Tarahumara, a near-mythical tribe of Stone Agesuperathletes. The Tarahumara (pronounced Spanish-style by swallowing the “h”: Tara-oo-mara)may be the healthiest and most serene people on earth, and the greatest runners of all time.

　　When it comes to ultradistances, nothing can beat a Tarahumara runner—not a racehorse, not acheetah, not an Olympic marathoner. Very few outsiders have ever seen the Tarahumara in action,but amazing stories of their superhuman toughness and tranquillity have drifted out of the canyonsfor centuries. One explorer swore he saw a Tarahumara catch a deer with his bare hands, chasingthe bounding animal until it finally dropped dead from exhaustion, “its hoofs falling off.” Anotheradventurer spent ten hours climbing up and over a Copper Canyon mountain by mule; aTarahumara runner made the same trip in ninety minutes.

　　“Try this,” a Tarahumara woman once told an exhausted explorer who’d collapsed at the base of amountain. She handed him a gourd full of a murky liquid. He swallowed a few gulps, and wasamazed to feel new energy pulsing in his veins. He got to his feet and scaled the peak like anovercaffeinated Sherpa. The Tarahumara, the explorer would later report, also guarded the recipeto a special energy food that leaves them trim, powerful, and unstoppable: a few mouthfuls packedenough nutritional punch to let them run all day without rest.

　　But whatever secrets the Tarahumara are hiding, they’ve hidden them well. To this day, theTarahumara live in the side of cliffs higher than a hawk’s nest in a land few have ever seen. TheBarrancas are a lost world in the most remote wilderness in North America, a sort of a shoreboundBermuda Triangle known for swallowing the misfits and desperadoes who stray inside. Lots of badthings can happen down there, and probably will; survive the man-eating jaguars, deadly snakes,and blistering heat, and you’ve still got to deal with “canyon fever,” a potentially fatal freak-outbrought on by the Barrancas’ desolate eeriness. The deeper you penetrate into the Barrancas, themore it feels like a crypt sliding shut around you. The walls tighten, shadows spread, phantomechoes whisper; every route out seems to end in sheer rock. Lost prospectors would be gripped bysuch madness and despair, they’d slash their own throats or hurl themselves off cliffs. Littlesurprise that few strangers have ever seen the Tarahumara’s homeland—let alone the Tarahumara.

　　But somehow the White Horse had made his way to the depths of the Barrancas. And there, it’ssaid, he was adopted by the Tarahumara as a friend and kindred spirit; a ghost among ghosts. He’dcertainly mastered two Tarahumara skills—invisibility and extraordinary endurance—becauseeven though he was spotted all over the canyons, no one seemed to know where he lived or whenhe might appear next. If anyone could translate the ancient secrets of the Tarahumara, I was told, itwas this lone wanderer of the High Sierras.

　　I’d become so obsessed with finding Caballo Blanco that as I dozed on the hotel sofa, I could evenimagine the sound of his voice. “Probably like Yogi Bear ordering burritos at Taco Bell,” I mused.

　　A guy like that, a wanderer who’d go anywhere but fit in nowhere, must live inside his own headand rarely hear his own voice. He’d make weird jokes and crack himself up. He’d have a boominglaugh and atrocious Spanish. He’d be loud and chatty and … and …Wait. I was hearing him. My eyes popped open to see a dusty cadaver in a tattered straw hatbantering with the desk clerk. Trail dust streaked his gaunt face like fading war paint, and theshocks of sun-bleached hair sticking out from under the hat could have been trimmed with ahunting knife. He looked like a castaway on a desert island, even to the way he seemed hungry forconversation with the bored clerk.

　　“Caballo?” I croaked.

　　The cadaver turned, smiling, and I felt like an idiot. He didn’t look wary; he looked confused, asany tourist would when confronted by a deranged man on a sofa suddenly hollering “Horse!”

　　This wasn’t Caballo. There was no Caballo. The whole thing was a hoax, and I’d fallen for it.

　　Then the cadaver spoke. “You know me?”

　　“Man!” I exploded, scrambling to my feet. “Am I glad to see you!”

　　The smile vanished. The cadaver’s eyes darted toward the door, making it clear that in anothersecond, he would as well.