My bike and I have been skidding and sliding for an hour on this one-lane, dirt-and-rocks, switchback-ridden road, an epic abyss yawning on my right flank, then my left, then my right again. The boulder-and-cactus panorama is unmarred by guard rails or anything that might interrupt a fatal fall.

But the steepest stretch comes just after the roadside shrine. In the next nine skittering, jouncing, knuckle-whitening, pebble-spitting miles, I'll be sinking 3,000 feet.

The canyon, which is really a collection of seven great gashes between stony, carrot-hued walls of the Sierra Madre Occidental range, more than fits his topographical bill.

As millions of Mexican schoolchildren could tell you, it's deeper than the Grand Canyon, and, depending on who's counting, it covers twice as much territory, or four times, or 10 times. The big ditch up in Arizona gets no deeper than about 6,030 feet. Here the slopes drop 6,135 feet from promontory to valley floor. And, best of all, you're allowed to ride here.

This is the type of plunge mountain bikers notice, and from the trails to the towns, there are signs of a hub in the making.

A new hub surfaces

Once upon a time, there was a town in Utah called Moab, a red-rock desert hamlet known for just one thing: uranium mines. Then somebody noticed all those old mining roads and the way a set of knobby tires could grip that red rock, and pretty soon Moab was mecca for mountain bikes.

Copper Canyon, is another Moab waiting to happen. Until now, if you've heard of Copper Canyon at all, it's probably because of the railroad — a 400-plus-mile trip from Los Mochis to Chihuahua full of tunnels, twists, track-side vendors in native garb and hints of the territory's history as a gold- and silver-mining region in the 18th and 19th centuries.

But more and more Mexican and American bikers are turning up these days, drawn by some of the deepest downhill runs in the world and a trail network blazed by generations of Tarahumara. The result is a landscape full of lethal vistas, backcountry characters and ancient ways.

Some drive from Tucson or El Paso, so they can bring their own hardware. Others fly into Los Mochis, near the Pacific coast, take the trains, then rent bikes. On the main drag in Creel, the canyons' gateway town, bike-rental income for Tres Amigos Canyon Expeditions' bike shop was $150 in July 2003 and $1,500 in July 2004.

Most riders don't even try, or make it less than halfway. From canyon floor to the beginning of paved road, it's about 40 miles, including some 9,000 feet of climbing. Nine years ago, Colorado-based mountain-biking champion Sarah Ballantyne made the climb in about 4 1/2 hours and most strong riders take five or six.

Well-traveled trails

The road from Creel to Batopilas is the marquee attraction of Copper Canyon mountain-biking. But for more technical thrills, dodging boulders, ducking branches and clinging to single-track paths, riders head for obstacle courses such as the aqueduct path on the Batopilas canyon floor or, up near Creel, the Valley of Monks, the Ejido San Ignacio. Or there's Cusárare Falls, where a rock-strewn two-mile route leads to a waterfall 90 feet wide and almost as high.

Though the landscape between Creel and Batopilas shows few obvious signs of environmental damage to a newcomer, the mining and logging industries have had their way here for more than a century.

Only one relatively small portion of the area is designated a national park, with much of the rest of the land communally owned by families that have farmed or logged here for generations. Those same families have kept the trail network operating with their daily travels on foot and horseback.

When I ask if anybody worries about bikes doing damage to the terrain, the locals look at me as if I've just voiced concerns about stray comets. Amid these sudden cliffs and cactus spines, protecting yourself from the landscape is still a far higher priority than protecting the landscape from yourself.

The scene makes a poster picture of back roads mestizo Mexico, part old agriculture, part new tourism. But look far enough down the trail, in either direction, and you find another civilization entirely: the Tarahumara.

They number about 50,000. They farm, whittle wood, weave baskets, sell crafts in the towns and walk miles and miles in brightly dyed fabrics and sandals made from recycled tires. Once or twice a year, the Tarahumara join in epic trail events of their own, kicking little wooden balls on paths for as long as two days straight. On a race of more than 100 miles, few on Earth can match the swiftest Tarahumara. Yet between races, several locals told me, nobody trains — they just walk, hour upon hour, up and down these killer slopes.

When Tarahumara men cross paths, anthropologist William Merrill wrote in the 1980s, their most common morning greeting is "What did you dream last night?"

Tarahumara kids seem more interested in reality. They want pencils, candy or a chance to check out a foreigner's wheels. Because even the Tarahumara have been buying bikes.

Just as the Tarahumara see the world a little differently, they handle their wheels their own way. Many Tarahumara bikes have neither hand-brakes nor pedal brakes. To slow down, the kids stand up on the pedals, bend a knee and reach one foot behind the seat, like a napping flamingo. Then they press their tire-tread sandal against the rear tire, applying rubber tread to rubber tread. And they do it with absolute ease.

'A different world'

It's been about 20 years since the first mountain-bikers found this territory and started talking up its possibilities. By the 1990s, a pioneering entrepreneur named John Saliba was bringing American mountain bikers almost every month in winter. Then two years ago Saliba died suddenly, at 33, on a trip to Thailand. To some degree, the American tour operators are picking up where Saliba left off.

Several guides say they see big possibilities in a long-idle 130-mile trail that mule teams once used to carry silver from the mines in Batopilas to the bank in Chihuahua. A bike-and-hike expedition reblazed the trail in November — a dollop of government funding is rumored to be on the horizon — and Outpost Wilderness Adventure may add it to their trip schedule next winter.

But none of this means the trails are teeming. Though the Mexican interior is crawling with Americans who sleep soundly in $12 backpacker lodgings, most would sooner fill their iPods with Milli Vanilli than risk their necks on a downward-hurtling bike.

Conversely, though plenty of mountain bikers stand ready to hurl themselves down any steep, rocky slope in the Lower 48, many are spooked by the idea of travel in rural Mexico.

These are not entirely unfounded fears: The U.S. State Department warned in January of escalating violence among drug traffickers in Mexico's border areas. Though we're well south of the most troubled areas, locals will acknowledge (if you leave their names out) that many Batopilas residents, in the absence of other options, make their living by cultivating marijuana in the canyon.

Courtesy of the Los Angeles Times