WE HADN'T BEEN ON THE mountain 24 hours and it was clear we were incompatible.

Twight bawled for a halt. I peered over my shoulder. He had slumped onto his sled and was glowering at me. I undid my waist belt and slid off my pack, unhooked myself from the sled, unclipped my harness from the rope, unclipped the rope from the ascenders, unsnapped both feet from my skis, and walked back down the glacier. I stopped whistling, wiped the grin off my face. Already I knew my piping of old rock songs was driving him crazy, my grin an affront.

“I hate, hate, hate this!” Twight was vitriolic. Not for the first time, he cursed our “stupidly heavy” sleds and packs and his blisters and our fast pace.

I walked away.

Another team of mountaineers had stopped ahead of us on the trail. They were playing football with a bag of food, stumbling hilariously in their huge boots in the wet snow. I made an interception, tripped, and fell face-first, using my head like a shovel. Hoots of laughter went up. Lifting my snow-caked self, I glanced back at Twight. He was still sitting on his sled, hunched and brooding, like a grim statue.

I turned and surveyed the desert of snow. Something in the soft dunes of the glacier looked familiar and I realized I had been here, precisely here, before. Two decades ago to the day, in fact.

THE GLACIER is scalding white, the sun a conflagration. An avalanche booms off a ridge far in the distance. Mike is caught with his pants down, straddling a crevasse. He leaps to his feet—harness and rope and wool pants and long underwear swaddled around his ankles—pirouettes, throws his arms out, and croons in falsetto:

“The hills are alive/With the sound of music!”

I bullet a snowball at him, triggering a flurry worthy of the wars we waged as kids. A hasty truce is called when two men appear on the horizon. We quickly don our huge packs, hitch ourselves to our ghastly haul bags, and lean into the traces. The climbers soon ski up to us, red plastic sleds wagging like tails behind them. Both men look familiar but I don't know why. The younger one has blond hair, the older black. We ask them what route they climbed.

“West Butt.”

“We're heading for the Cassin Ridge,” I blurt.

They glance at each other. The stocky, sandy-haired one nods and says, “Doing it the hard way, I see.”

Mike and I don't know what he's talking about. He points to our homemade, 100-pound haul bags.

It is the first day of our first expedition and already we have learned something: Our haul-bag theory doesn't work. We thought nylon bags would glide along the glacier. They don't. They plow, cutting foot-deep furrows in the snow, and this only by dint of us straining like draft horses, sweat gushing from our pores.

Perhaps it is our imbecilic, Huck-and-Tom enthusiasm. Perhaps they see in us something of themselves whenthey were young and inescapably foolish. Perhaps theysimply can't stand stupidity in the mountains and feel a duty, as fellow climbers, to keep us from getting a herniaon day one.

“Come back to base with us,” says the dark-haired, deeply tanned, older one, “and you can have our sleds.”

We abandon our bags and ski with them the six or seven miles back to the airstrip-cum-base-camp. Turns out these two had also set out to climb the Cassin, but storms and cold had made it so dangerous they'd taken the trade route up Mount McKinley instead.

At base they empty their kid sleds and give them to us. It's an act of goodwill, a handoff from old partners to young partners. We say thanks, shake hands, and ask their names.

“Yvon Chouinard.”

“Rick Ridgeway.”

SOMEBODY yelled and I arced the food bag back.

Twight was on his feet. We ground onward, two dark spots in a sky-size expanse of ice. Start and stop. Start and stop. Finally it was senseless to continue. We veered off to an abandoned, three-sided snow wall, dug out the drifts, and set up our tent. We were at 10,000 feet, already a day behind, but still intent on a quick ascent of McKinley—a few days acclimatizing on the West Buttress, perhaps a few days sitting out storms, then a three-day push up the Cassin.

In the morning we decided to make a cache to cut weight.

“This is way too much food,” said Twight.

“Probably.”

“No. This is fucking stupid!”

We had bought the food together. Two hours caroming down the aisles in a Colorado Safeway, pitching whatevereither of us wanted into the shopping cart. It was fun. We'd never climbed or hiked or even drunk a beer together before that. When the cart was full we figured we had enough. We split the food in the parking lot and parted. I was pleased to see how nonchalant he was about it all. It boded well, I thought. A week later we met in Anchorage at midnight, drove to Talkeetna in the wee hours, and were slowly skiing up the glacier later that same day.

The food bags were labeled “brkft,” “lnch,” and “dnnr.” Twight muttered, dumped all the bags out in the snow, and started sorting the food one package at a time. Two hours later, we still had several heavy bags of food left to take up the mountain—which only made sense given it was just day three of a two-week expedition.

“It's still too much,” groaned Twight.

“Fair enough.” I grabbed one of the larger bags at random and threw it on the cache pile.

“What are you doing?” Twight was incredulous.

“Cutting weight.”

In the end the bag went with us and our sleds remained too heavy and Twight started in again ten minutes up the trail. I stopped and told him I was ready to cut all the food. Cut the sleds, cut the packs, cut the rope.

“Take a water bottle, a candy bar, go for the summit from here.” I was serious. I'd done it before on a dozen mountains. Twight thought I was mad.

Climbing the Cassin had been my idea. I'd asked Mark Twight to be my partner because he was a bold alpinist known for climbing fast and light, an ascetic philosophy I live by. But alpinism and mountaineering are not synonymous. Mountaineering—even if it's only a means to set up for a fast alpine ascent—often entails slogging under heavy loads for numerous days. Twight, as he later told me, abhorred slogging.

I, on the other hand, abhorred whining. Hence, though we may have been matched in philosophy, in temperament we grated on one another like fingernails on a chalkboard.

In many ways a climbing partnership is no different from any other intimate relationship. You sleep side-by-side, eat from the same pot, piss in the same spot, live cheek-by-jowl day in, day out. It's not enough that your heads be together, your hearts must be as well. Even in the mountains, the fabled redoubt where one wrong step can spell the difference between life and death, technique means less than companionship. And companionship is a matter of chemistry. Mysterious and invisible. And we didn't have it.

“So what do you say?” I shouted.

Twight said he did not intend to go any faster or lighter than he was going.

“BLACKBIRD SINGING in the dead of night…”

“Take these broken wings and learn to fly…”

We're alternating lines, harmonizing on the chorus. In a rare moment of reasonableness, Mike and I have decided that if Chouinard and Ridgeway found the Cassin too risky, we probably would too. We're bound for the West Buttress instead. Hammering up the glacier, we keep the rope taut between us, like a ligament connecting two bones that form one joint. We move at the same pace. We have always moved at the same pace. We can't imagine it otherwise. We have been partners since boyhood.

In high school we double-dated, built snow caves, climbed the local crags. After high school we lit out to see the world. Hitchhiked across north Africa, got arrested in Russia, hopped trains across Europe. When our money ran out we took to sneaking into university cafeterias in Milan, Barcelona, and Paris, where the girls were gorgeous even if they ignored us.

Back in the U.S. it was summers in Yosemite or Joshua Tree or the Tetons, winters ice climbing in the Rockies, arguing ceaselessly about Sartre or sex. When we latched onto the idea of climbing McKinley we were penniless college kids clothed by the Salvation Army. We sold T-shirts for funding and sewed all our own equipment: eccentric, outlandish jackets, homemade backpacks. What we had to buy we bought used. Leather, full-steel shank, 15-pound Frankenstein double-boots. Heavy downhill skis with first-generation Ramer bindings. Salewa ice screws. Miserable, even dangerous, gear. But what we lacked in accoutrements we made up for in a partnership of perfect pitch.

FROM 10,000 FEET, Twight and I hauled to 11,200, made a carry up around Windy Corner to the 14,200 camp, and then came back down for the night, stashing our skis in the snow at 12,500 just above Squirrel Hill. The next day it was storming, but Twight and I couldn't bear hanging out in the same tent together, so we moved up toward 14,200, hardly speaking. The day before, both Squirrel Hill and Windy Corner had been so icy we were obliged to strap on our crampons and carry our skis. Thus, when we reached the skis the next day, I suggested we leave them there. We would only carry them up and then carry them down, hardly using them again. Twight didn't respond. He just started loading his boards onto his sled.

“Hey!” I said, shouting into the wind. “We're having a discussion.”

“I'm not!” Twight shouted back. “I've decided.”

“For yourself, or for the team?”

He gave me a quizzical look, and I wondered if it had never occurred to him that we were a team, or perhaps even that mountaineering is a team sport.

“Point taken,” he screamed, and finished strapping his skis to his sled.

Later he shared his lunch with me. It was a peace offering, and as we ate, I began to realize that he wasn't enjoying my company any more than I was enjoying his. This climb was only a warm-up for Twight; in June he planned to attempt an extreme route on McKinley's South Face (and would succeed).

I was mulling over our unexpected discordance when, halfway through the corridor of crevasses on Windy Corner, it struck me that I didn't have a clue why Mark Twight climbs. For 25 years I had believed that climbers climbed for the same reason that painters painted or writers wrote or composers composed: because they loved it.

How absurdly callow.

THE STORM ATTACKS out of nowhere. Mike and I don't know where we are on the mountain. We don't know we're on Windy Corner, the worst possible place to be in a storm. We dig in immediately, hacking a shallow shelf in the steep slope, hastily surrounding it with blocks of snow and throwing up our laughable A-frame pup tent. We use our ice axes to stake down the fly, but it flaps as violently as a trapped bird.

We tie the two plastic sleds to the ice axes—and there they snap horizontally in the wind like red flags—then fill the tent with everything else and dive inside. We have frostnip on our hands, fingers, and faces. We clamp our hands under our armpits and put our bare feet against each other's bellies. When our hands warm up we press them against the patches of frozen white flesh on each other's faces. After all body parts are thawed, we rewarm our mittens inside our parkas, plug them on, and take up our stations at either end of the tent. Fearing that the wind is going to tear the tent right off of us, like a tornado lifts away the roof of a house, we hang on to the poles.

We hold down the tent all night. Telling every dirty joke we know. Telling stories, usually about each other, that to us are so funny we double over in laughter.

THERE WERE PERHAPS 100 climbers camped at 14,200 in late May—a multinational village of Czechs, Swedes, Slavs, Canadians, Welsh, Americans, French, Brits, Aussies, and Japanese, from 8,000-meter summiters to hikers who had never worn crampons—and the mountain brought us all to our knees. It was viciously cold. The cold stripped us all, easily and quickly, of our pretensions and destroyed any hierarchy, real or ego-induced. Every last one of us was just hoping to summit via the easiest path possible and get down.

Once again it was the mountain that called the shots. The intense cold made the Cassin, a finesse route that could require technical rock climbing in thin polypro gloves, out of the question. Twight and I briefly considered the West Rib or the Messner Couloir, but both had two feet of avalanche-prone windslab over blue ice. We made three fast—sub-three-hour—acclimatization climbs up to 17,300, unroped and barely together. Twight borrowed a spare tent from a fellow climber so we no longer had to share our little icebox. I awoke early and cooked breakfast; Twight cooked dinner wearing earphones. I spent our rest days wandering around camp talking with other climbers. Twight hung out at the Park Service rescue station or stayed in his tent.

One night around the campstove I asked him what he was thinking about and he said, “About when this trip will be over.”

CAMP 14,200 IS buried under four feet of snow when Mike and I reach it, the few tents crushed. We excavate a hole, put our tent inside it, and start winter camping for a few days.

“You know, Marco,” Mike says, “it was only 40 below last night.”

“Man, home's colder!”

It almost was. The previous winter, to prepare for McKinley, we would ski into Rocky Mountain National Park every time an arctic storm blew down, camp for a week, and fight our way up frozen waterfalls. We both had read Minus 148: The Winter Ascent of Mt. McKinley, by Art Davidson, and considered the title's temperature our benchmark for when suffering should begin. Above that, we figured, it's all good times.

One morning Mike is not feeling so hot. Headache, nausea. I make a solo carry of food and fuel up to 16,000 feet. By the time I get back down, Mike is sick. Mortally sick. His face and hands are bloated, his breathing quick and bubbly, his movements simultaneously sluggish and jerky. We both realize—and will later confirm—that he has pulmonary and cerebral edema. We pack up and descend immediately, hoping to get down to 8,000 feet by midnight. We don't make it. A storm pounces less than an hour after we leave and we're forced to hide out in a collapsed igloo at 11,000 feet. For four days we can't even crawl out to relieve ourselves. We sing every song we know, trying to outdo the roar of the storm.

“Rocky Raccoon…”

“Checked into his room…”

“Only to find Gideon's Bible…”

Mike's condition doesn't improve, but it doesn't worsen, and that is enough. We both know our grand, inaugural expedition is over. No sweat, we've already planned the next one.

TWIGHT AND I SUMMITED, but not with each other.

We'd met two eager lads from Dartmouth, Bart and Fred. They were the same age as I was when I first came to McKinley. They too had dreams of doing the Cassin (and two weeks later would nobly fulfill them) but, like everyone else at Camp 14,200 at that time, they were bent on the West Butt.

Whenever Bart and Fred were around, Twight seemed transformed. He became animated and voluble; he even smiled. Nothing close to the guy I'd been climbing with. Fred, in particular, was star-struck. He'd read Twight's recent mountaineering manifesto and was thrilled to meet the guru in person. Twight responded warmly.

One morning we set out for the summit as a foursome. But at 17,000, Bart started slowing down. He was clearly suffering from inadequate acclimatization, couldn't catch his breath, and thus couldn't keep up. Fred, far out ahead with Twight, saw that Bart and I had taken up together, talking and moving steadily. Twight and Fred went from 14,200 to the 20,320-foot summit and down in ten hours; Bart and I, discussing family and fathers along the way, did it in eleven. Twight had a cup of hot soup waiting for us when we got back to camp. Everybody was happy. It was minus 37 the morning we set out and minus 39 that night.

On the summit, lumpy clouds had rolled in, making the highest mountain in North America appear to be just another nondescript bump of white. I was thinking about Mike. About all the expeditions we did together. About friendship. About how, as a young man, I knew, instinctively, that it was the partnership, not the peak, that mattered.

Companions in Misery