The wind is blowing at 60 knots, gusting to 70, and we're walking this broad, yellow plain, and we're going fishing, Yvon Chouinard and I. Ahead of us, a dust storm rises and screws its way upward into the blue sky. Chouinard says, "You can feel it." Feel what? "The fishing is going to be shit-hot today," he declares, smiling. "It feels like that moment before an avalanche."

Green carnations of foam are exploding across the Río Grande as the river surges through the bare Patagonian hills. Beaten by the wind, it almost appears to flow backward, as if surrendering and retreating to its source in the foothills of the Andes, across the Argentine border in Chile, 30 miles away. This is sacred country to Chouinard, his favorite wilderness, and each year he stays at a lodge called Villa Maria to fish this remarkable river, recognized as the best sea-trout water in the world.

Chouinard punches merrily through cyclonic blasts of wind, his fly rod quivering: He's happy under these conditions – typical of Tierra del Fuego – not because they're inherently dangerous, but because they'll make the fishing more challenging.

"Incredible!" exclaims Chouinard. "You gotta love it! Unbelievable!" He looks back at me, grinning wildly. "What doesn't kill you makes you stronger, right?" And I can't help but grin, too. I hunch over, pull down my hat, and try to keep up with him.

Which is when Yvon Chouinard – supremely fit and tanned at age 60; a pioneering mountaineer; an expert fisherman, kayaker, and surfer; a blacksmith and a gourmand; a lover of Beavis and Butt-Head and the poetry of Charles Bukowski; an environmentalist, an entrepreneur, and the founder of the clothing company Patagonia – stops to study the river thoughtfully, and then steps off the bank into thin air, to catch the biggest trout on Earth.

In a world of shrinking horizons, Yvon Chouinard has come to embody something near-mythic: a life lived hard-on-the-edge, perfectly and gracefully. These days, even as supermodels sport Patagonia jackets at art galleries, climbers are still wearing them on Everest. Almost single-handedly, and with just a handful of patents, Chouinard has democratized adventure by inventing and manufacturing outdoor clothing so effective that even your grandmother might survive a journey to the North Pole in it.

In many ways, Chouinard wishes this were not the case. "An adventure is what happens when you screw up," he tells me. He insists that adventure is something you'll never really find on prepackaged trips or by donning one of his mountain parkas. Still, he acknowledges that he's selling a dream: "Everyone wants to play."

He speaks politely, with a tiny drawl – perhaps the way Henry Fonda would have sounded if Henry Fonda had been a California-bred surfer. Now, however, Chouinard is a surfer whose company tallied sales of $180 million last year, and who is quite possibly having as much fun as anyone on the planet. He's climbed in Nepal and Chamonix. He has skied the Alps. Lately, he's surfed in Australia, salmon-fished in Iceland, and bonefished off Christmas Island in the Pacific. Next, he's planning a trip to Chile and a 46-day trek through China. Between expeditions, Chouinard kayaks rivers in the American West and surfs the point-breaks near his solar-powered house just north of Santa Barbara.

Of course, his life hasn't always been fun. During the '80s, Patagonia's ­profits soared, but in 1991, recession forced Chouinard to lay off 120 of his 620 employees, a step that he found extremely painful, priding himself as he does on providing a vibrant and supportive work environment. He emerged from the crisis with a bold purpose: He would change American business by using Patagonia as a model of "sustainable industry," one that neither harms the environment nor grows so quickly that its own viability is jeopardized.

Patagonia shirts and pants are now made of organic cotton, its jackets are spun from recycled plastic bottles, and Chouinard annually donates more than a million dollars to eco-groups that otherwise might receive no funding at all. Business schools invite him to lecture; Yale has awarded him an honorary degree (doctor of humane letters); and President Clinton has praised him as a "responsible corporate citizen." He counts Tom Brokaw, Harrison Ford, and novelist Tom McGuane among his friends. Life is good.

Yet the good life for Yvon Chouinard has little to do with the cachet of running a multimillion-dollar company. He has always preferred to categorize himself as a craftsman-turned-businessman. Even now, he refuses to read the business section of a newspaper, so Malinda, his wife of 30 years, peruses it for him. You learn that he doesn't have a savings account because he plans eventually to give everything away. He dreams of living on $200 a month, without electricity and eating whatever he can raise in a garden or catch by fishing. He dreams, in the end, of owning absolutely nothing.

Which is partly why he loves Tierra del Fuego. On the Río Grande, he's in search of what he has always looked for outdoors: the Perfect Moment, a flash of "lucidity, focus, and emptiness," the psychic intensity that hardship brings. But there's a slight problem. Though the fishing has been great – superb, in fact – the Villa Maria, part of the historic Estancia José Menendez, a ranch outside the town of Río Grande, has come to seem, well, too plush. Chouinard wants something more. He wants to test himself, even in his favorite place. He wants more hardship, period. His longtime fishing companion Tom McGuane explains it like this: "Whenever he gets comfortable, he gets suspicious of everything, and he sort of smells a rat. We have a camp on the Dean River [in British Columbia] where we have warm beds and where somebody cooks for us, and I know that bothers him." McGuane adds: "He always wants to do things the hard way."

So we'll fish the Río Grande in comfort for now, and then we'll do something Chouinard has always wanted to do: We'll disappear up a nearby river that he once glimpsed, for a moment, from an airplane, and whose image has lain in his memory, burning and beckoning. We'll scrounge for food and eat with our fingers; we'll sleep under the stars beside the silver river. Maybe we won't catch anything at all. We'll suffer; we'll know happiness.

It's now midday at a pool called Nirvana, and Yvon Chouinard has just hooked a trout. It's a big one, getting bigger as he reels it in. Chouinard's back is curved like a violin, his knees are braced against the current, and he's not making a sound. The fish's only apparent effect upon him is registered in the flexing of his jaw muscles, in the minute adjustments of his black eyebrows. All morning, we've been blasted by the howling, line-tangling wind, and I've caught zip. Chouinard has landed and released three gorgeous brown trout, none under 15 pounds.

Then, as if no longer able to stand his own concentration, Chouinard lets out an invigorating chortle, crescendoing into a cry that his friends later describe to me as his "cave-man laugh," as in: "AHHHH ... HAAAAA!" It's startling, to be sure, yet so heartfelt that you can't help but love it.

"God, what a trout!" he says. The huge silver fish leaps and then drops back from its skyward course as if repelled by the sun, descends beneath the surface, and holds there, trembling, on the river bottom. Chouinard kneels, cradles the exhausted fish – which he guesses weighs 20 pounds – and rocks it gently in the current. A fish to remember.

"You know," he says, after releasing the trout, "fishing this place is one of the few things in life that keeps getting better. When I first came here in '68, I thought I was stepping back in time."

That year, Chouinard – along with Doug Tompkins, the founder of the North Face; champion skier Dick Dorworth; climber/filmmaker Lito Tejada-Flores; and an English climber named Chris Jones – piloted a secondhand van 18,000 miles from California to Mount Fitzroy, about 400 miles from where we are now. The journey, which took six months, was a traveling circus of surfing, skiing, and mountain-climbing – a road trip à la Neal Cassady, with a soundtrack by Mingus. "The whole point of the trip," jokes Chouinard, "was a search for the perfect flan."

In its scope, the excursion was akin to taking a hang glider to the moon. The group's successful ascent of the 11,000-foot Fitzroy – the third ever – took 60 days, many of them spent trapped in snow caves by hideous weather. On the summit, the four men unfurled a flag that read "VIVA LOS FUN HOGS!" It was a landmark climb; no American had ever summitted Fitzroy before. "It really opened up Patagonia," says Dorworth. "It really changed our lives."

You might think Chouinard was a bankrolled hippie with a lot of free time on his hands; actually, he was the son of a French-Canadian couple of limited means. Chouinard recalls that, as a young boy, he watched his father sit down with a bottle of whiskey and a pair of pliers and pull his own teeth – all of them – because he felt the dentist was charging too much for dentures. "Because I inherited some of these genes," Chouinard wrote years later, "I have a preference for learning and doing things on my own."

He discovered climbing while pursuing falconry, which he'd taken up at age 12, rappelling to the birds' nests high in the mountains of the San Fernando Valley. By 1957, when he was 19, he had already revolutionized mountaineering by creating a piton that could be nailed into and then removed from rock, unlike the European kind, which had to be left in place. He could make two in an hour on his portable forge, and he sold them from the trunk of his car for $1.50 each.

"His first ascent of El Capitan was, in its time, the hardest climb in the world," says Tom Frost, a photographer and fellow gearhead who accompanied Chouinard in 1964 as he pioneered a route up the massive North American wall in Yosemite. In 1968, the year of his epic journey with the Fun Hogs, he finished designing his now-legendary climber's ice ax, one of which is included in the Museum of Modern Art's permanent collection. When he wasn't pushing the limits of his craft, Chouinard would sit around Yosemite's infamous Camp 4, the vortex of America's burgeoning climbing scene, copying aphorisms from books he was reading – Camus, Nietzsche, the poetry of Robinson Jeffers. He was cultivating a lifelong credo, he says, based on Zen-like ideas of simplicity and impermanence.

"Every one of those friends of mine... [we] never wanted to work, we never wanted to become stable citizens. All we wanted was to climb, forever. It was as valid a life as anything we could think of."

Some stories people tell about Chouinard: "I remember one time we were on the Kautz Glacier in Washington, and I'd had what I call the 'Three-Minute Yvon Chouinard Short Course in Crampons,'" says Tom Brokaw. (Together, Brokaw, McGuane, and Chouinard constitute a sporting threesome they call the Do-Boys.) "We were [crossing] this very treacherous stretch of black ice, and if you slipped, it was at least 2,000 feet before you'd stop. So I turned to Yvon and said, 'Shouldn't we rope up together here?' And he said, 'NO WAY! If you go, I go!' He said, 'This is just like getting a taxi in New York! It's every man for himself!' There's no bullshit factor when you're with him. With Chouinard, you can either do it, or you can't. And I live in a bullshit world," says Brokaw, laughing, "so it's a perfect antidote to that."

"It's Brokaw's stories that have kept me from similar adventures," says Harrison Ford, a neighbor in Jackson, Wyoming, where Chouinard owns a home. This month, Ford will present Chouinard with the Riverkeeper Environmental Excellence Award for his conservation-minded work ethic. "I've gone fishing with Yvon and I've played tennis with him," says the actor, "but I have not gone up a mountain with [him]. I don't trust Yvon to know the limits of a natural human being."

"One day he was looking at the magazine Earth­watch," says writer Rick Ridgeway, "and it had this picture of a spire on this island, and he said, 'Hey, we oughta climb that sucker.'" It was 1988, and Chouinard, at 50, had begun to wonder if he still had his edge.

A few months later, Chouinard and Ridgeway, with Doug Tompkins and Jim Donini, a fellow climber, were on a fishing boat steaming from Puerto Natales, Chile, in search of the unnamed peak. They didn't even have a map. The captain steered for the island by looking at the photo Chouinard had ripped from the magazine.

"The boat left us on this uninhabited archipelago with a month's food, our climbing gear, and our kayaks," says Ridgeway. "We didn't even know if we were in the right place." After a few days, the weather cleared – and there was the peak, right above them. But the wind had kicked up, blowing so fiercely that every time the men tried to stand, they were knocked to the frozen ground. They spent two weeks hunkered in tents, waiting.

As soon as the weather broke again, Donini and Chouinard quickly began an ascent, both thinking they'd make a few pitches, look around, and return to camp. Soon, the men passed some mental point of no return. They continued climbing for 14 hours, hammering pitons and fixing ropes, finally summitting the 4,000-foot peak in frigid darkness.

Chouinard and Donini were forced to crawl back down the mountain through the night. Ridgeway and Tompkins were lying in their tents, weeping, certain that their friends were dead. In the morning, the two half-frozen climbers reappeared, their clothes shredded. And now they faced a 75-mile paddle to the mainland.

"The winds were so strong," says Ridgeway, "that you had to do everything to keep from flipping over. Chouinard was flipped in one of the worst gusts, and it just held him down." Bobbing in an ocean laden with icebergs, he turned hypothermic but managed to climb back onto the upturned boat and paddle himself to a nearby island, where his friends built a fire to thaw him out. They finally made the mainland the next day.

"I really scared the shit out of myself on that climb," Chouinard tells me. "Before, I'd always had enough to take it right to the edge. I came too close to going over."

"When we pulled the kayaks up on the beach in Ushuaia," says Ridgeway, "we all looked back at what we'd just come from. And I'll never forget it: Yvon suddenly got this big grin on his face. And the first thing he said was 'Well, that's just what I needed!'"

It's 10 minutes to dusk, and I've been watching Chouinard fish, feeling compelled to be better than I am, which is the signature effect of his life. We're standing at a pool called the Secret Spot, waiting for what Río Grande fishermen call the Magic Hour, the silken time just before dark when the fish bite readily. I ask Chouinard for a casting lesson.

You catch these capricious Río Grande trout by plopping your fly on a far bank and drifting it into the current in a steady pattern: cast, drift, take two steps downstream, then repeat. But my fly line swims skyward with each thunderous blast of wind. Part of the problem is that, with my smaller 8-weight fly rod, I'm underpowered: De rigueur on the Río Grande is the longer power-stick known as a double-handed spey rod – like Chouinard's – which can drive a fly line through a brick wall.

Chouinard proceeds to demonstrate the balletic moves of spey casting, praising me when I nail it. Soon, I halfway have the hang of it. Chouinard told me earlier that rock-climbing was about "making links," about finding a zone and wasting no effort. "Fishing," he said, "is like that, too."

As I stand on the riverbank, thinking about this, I start casting in a new rhythm, a new zone, reaching water I haven't reached before. Still, I can't touch the Secret Spot completely, so I cross the river and climb the opposite bank, as Chouinard did that morning. On my second cast, the line comes tight. I can tell the fish is big, but who knows how big? It's dark. The trout sulks on the bottom. Finally, I turn him, and he rises slowly. As he swirls in a blurred pane of moonlight, I see he is the biggest trout I will catch in my life.

Crossing the river, Chouinard calls "Hey, Doug! Way to go!" And the trout, with a beat of its tail, runs up the stony beach and comes to rest at my feet: a male weighing 25 pounds.

"My God," Chouinard says. "Look at that fish!" He shakes my hand, telling me maybe 20 people out of the hundreds who have visited the lodge in its 10-year history have caught a brown trout as enormous as this one. That night, Chouinard toasts me over dinner. We seem ready for the river of his memory, for still more unexplored territory.

Look at these hands!" It's early morning, and we're heading down an empty gravel road into the interior of Tierra del Fuego, to the secret river. "Paper cuts!" Chouinard is saying. "I've got paper cuts! All I do is work!" He can't wait now to suffer, can't wait to sleep on cold dirt under the stars.

The road rises past tin houses that rattle in the cold wind. It's a sound that maybe only 10 people a year get to hear, the landscape is that empty. Sheep and cattle scatter as we pass. After two hours, we arrive at the 50,000-acre Estancia Marina, southwest of Río Grande.

Yes, he will lead us to the river, the estanciero – the owner of the ranch – tells us. "I have no idea if it's got fish," he says, "but, please, be my guest, fish it. And tell me if it's any good."

This idea of an unfished river astonishes Chouinard, and we follow in our rented pickup as the estanciero leads us along a path through dense stands of beech trees that seem to close behind us as we pass – I begin to imagine that we'll never find our way back. The sun is warm on our faces, and I look up and see the snow on the mountains and feel the cold wind and hunch down in my jacket and feel lonely and happy all at once. Chouinard says, "Jesus, what country, what country." At a camp on a hill above the river, we build a fire at dusk.

Across the water, we can see a kind of tepee, a 40-foot cone of carefully arranged logs – the former home, the estanciero told us, of the last Ona Indian to have lived in Tierra del Fuego, dead for some 20 years now. The story may or may not be apocryphal, but the tall, blackened doorway suggests an uneasy emptiness, as if someone has just stepped back from it into the shadows. Wherever we look, we see it out of the corners of our eyes. "Spooky," says Chouinard.

At the campfire, Chouinard starts making dinner. He lays our steaks – the only food we've brought – directly on the fire's red coals. Even though I am aware that we have no plates or cooking utensils with us, I still can't believe what I'm seeing. I'm certain that our entire food cache is turning to cinders.

It's then that I realize we haven't brought any water with us either. In fact, I have outfitted myself for this three-day camping trip with nothing except a tent and a sleeping bag. Chouinard has brought along even less. "I didn't even buy a tent until I was 40," he explains. "I could always find a cave, or a tree, out of the wind..."

After a while, though, the lack of supplies doesn't trouble me. I start to think, Who needs all that shit? Chouinard is squatting by the coals, smiling at the glow. "This will work out great," he says. "I once taught a class about cooking outdoors without pots and pans. You can make bread, you know, just by using a stone." He snatches the steaks from the fire and sets them on a mossy log. They're not burned, and they're not coated with cinders. They're perfect, in fact. We eat in the dark with our fingers, tearing off pieces with our teeth.

At dawn, we find the fish. They're in six inches of water, hovering, as if in a clarifying fluid, along the banks. They seem to look up, unafraid, as we pass by. Maybe it's been years since anyone has walked here; maybe no one ever has. These are rainbows and browns, two, three, and four pounds each, and I catch five of them and keep one for dinner. I walk downriver as I cast, my head feeling as if it's bumping against the sky.

Chouinard, for his part, is being driven to his usual fits of ingenuity. Crouching on the bank in stealth postures, he tries sinking lines, then floating lines. Every few minutes, I hear him: "Ah, shit! Missed 'em! "Then: "Jesus, did ya see that fish!" It's an endearing lecture to himself, filled with wonder, as he catches one glorious fish after another. He walks up to me, smiling, and sits on the bank. "What a day we're having," he says. "We haven't seen another footprint. What a day." Winding up the slack on his reel, he stares at his rod, then finally gives it a jiggle. "This," he says, "is one of the best days of fishing in my life. Fabulous."

Before long, Chouinard is up again, walking and casting. At one point, a swallow lands on his fly rod, mistaking it for a tree branch, then disappears in a frantic burst of tiny purple wings. Chouinard catches so many fish he loses count: 45, 50, 65... . I can just barely see him now, walking downstream, bobbing in the waves of heat boiling from the valley floor.

Resting on the bank, I recall something Chouinard read to me, something he'd written about a climbing experience he'd had on El Capitan when he was young: "Nothing felt strange in our vertical world. Each individual crystal in the granite stood out in bold relief... . After a period of time, the artist gets caught up in the sculpture, and the material comes alive."

That afternoon, when we are driving out, picking our way down the valley and looking for our hidden passage back up through the beech forest, I point from the car window at the distant silver river threading through the green valley. Chouinard is staring at it, too – he has been glancing at the river the whole time he's been driving, not saying a word.

He turns slowly, as if he has just remembered that I'm in the car. His eyes are bloodshot, his lips are cracked, his face is baked red. He's been wasted by sun and wind. We both have.

"Tempted?" I ask.

Sitting up, he says, "Oh, yeah, I am definitely ready to play."