HIS was the Patagonia I had seen in all the documentaries, only better. A frosty wind blew into our faces as our group of 20 backpacking tourists climbed across ledges of sharp-edged ice on the vast Perito Moreno glacier crawling down South America's continental ice shelf.

The crampons attached to our shoes enabled us to walk up 45-degree inclines almost effortlessly, and then look down into cavernous icy ravines colored deep blue from mineral residues. As we turned a corner into an icy hollow with frozen peaks that soared 50 feet above our heads, our two guides had a surprise for us: a table graced by a single bottle of whiskey and a bag of chocolates. Nature provided the crushed ice, and it was most definitely time for a nip.

"Those who are still capable, let's move on," our head guide, José Pera, said with a laugh after a 10-minute break. No one stayed behind, of course, and an hour later we were on hard ground picnicking while watching shards of ice crack off the glacier's 160-foot front wall and splash mightily into a milky inlet of Argentino Lake.

It was the first of eight days of hiking, fly fishing, camping and horseback riding through Los Glaciares National Park in Argentina for my Peruvian friend Paola and me. Our lips were cracked, our cheeks were wind-burned, our legs and bottoms were sore, and our wallets were a good deal thinner by the end of our trip taken in mid-January, the middle of summer. But the pleasures of Patagonia's harsh terrain - often helped along by the knowledgeable and good-humored guides we hired along the way - made for a marvelous vacation of discovery, serenity and beauty.

The Perito Moreno glacier, its surface slightly larger than Buenos Aires, is fast becoming one of Argentina's most popular tourist attractions. The inauguration last November of a modern airport in El Calafate, a town just outside the park, now saves tourists a day of driving each way from Río Gallegos, on the other side of the province of Santa Cruz. Many travelers now stop in El Calafate for a day or two in between short flights to Tierra del Fuego and other Patagonian destinations. An afternoon visit to Perito Moreno - which can be viewed comfortably (without crampons) from a series of wooden platforms with a well-stocked snack bar - is alone worth the trip to El Calafate.

But we wanted to get off the tour bus and do more. It takes at least a week to see a park that encompasses 1.48 million acres of soaring granite peaks, emerald lakes and lagoons, beechwood forests and more than 50 glaciers advancing like rivers of ice down the Patagonian mountainsides and carving into wooded valleys. Traveling around the park is time-consuming and tiring. The drive on the bumpy gravel roads through the vast arid steppes between El Calafate and El Chaltén, a village on the north end of the park, takes four hours. And hiking from one campsite to another can take three hours or more, wearing heavy backpacks.

Paola and I were challenging ourselves to attempt things we had never done before. Our travel agent in Buenos Aires had arranged everything from standard tourist excursions to hiking expeditions, from a four-star luxury hotel to upland camping in the cold Patagonian nights. Days 1 and 2 were full-day trips to the Perito Moreno and Upsala glaciers that included a thrilling boat trip through a glacier iceberg field, a light hike to a pretty waterfall and a succulent barbecue lunch of lamb at the Cristina estancia, or ranch, a short drive from El Calafate. We spent three nights at the Hotel Posada Los Alamos in El Calafate, a comfortable and roomy Alpine-style hotel that serves hearty breakfasts and offers a well-groomed three-hole golf course.

The worst moment of the trip came when the front desk attendant called our room on our final morning at the hotel at 7:30 a.m. to say that our fishing instructor was waiting for us in the lobby. We had asked to be awakened an hour before, so we lost an hour of precious time packing and checking out. Our instructor warned us that we would probably miss the best fishing of the day before the winds whip up and the surface temperatures rise to send the trout deeper into the lake waters. But we carried on, counting on beginner's luck.

By the time we reached Roca Lake two hours later the winds were indeed whipping across the inlet, where geese and ibises fly gracefully together. Leo Colli, our jovial instructor, pulled out his colorful flies and patiently taught us the rudiments of casting. It seemed like a simple motion, but I had trouble getting the hang of it.

Leo suggested I hum a popular Strauss waltz while casting, which helped, but in the end I did not have much rhythm standing thigh deep in a freezing lake wearing heavy padded overalls. Early in the day, I did get three bites in quick succession, but each time I lost my trout. Cast, cast, cast I did, patiently, picking up weeds and rocks along the way. Once my rod came apart and my tackle knotted into a jumble. We caught nothing, and retreated to shore for a steak barbecue and siesta and finally to the cozy Nibepo Aike estancia for a day of riding and hiking, more roast lamb and sleep.

Refreshed and now fairly acclimated to the chilly weather, Paola and I were ready to explore the higher altitudes northwest of the giant glacial Lake Viedma, a mecca for mountain climbers from around the world who come to scale Mount Fitz Roy and Cerro Torre, two granite peaks that soar like giant needles into the sky. In the last 10 years the mountain climbers have been joined by backpackers, who are satisfied to trek to the bases of some of the most spectacular peaks in South America.

After a five-hour taxi drive from Nibepo Aike we arrived at El Chaltén, a village of 450 people dedicated to the tourist trade, and found that our hotel reservations for the final two nights of our trip had not been registered. But such details could wait. We had come this far to camp out.

Vicente Labate, a sinewy 28-year-old hiking guide, met us at La Aldea, a local lodge, and helped us pare down our belongings to the absolute minimum. We set out for our campsite near the shore of Capri Lagoon, a bit over two hours by foot outside El Chaltén. The fun began only minutes into our climb when we spotted two Andean condors gliding majestically above a valley.

"Come, come, come," Vicente said earnestly, his voice just above a whisper as he urged the birds to fly closer to us. "They are very curious about humans," he added.

We were lucky that we did not have to share Vicente with anyone else. His love of nature was contagious. Over three days we picked wild berries, listened for woodpeckers that often made the only sound in the forest audible over the gusting winds, and absorbed his lessons on natural history over a gourd of maté we passed among ourselves. Early one morning we shared Vicente's excitement when he noticed an odor vaguely like skunk; but it was actually the scent of fresh urine from the rarely seen pumas that roam the mountains at night. We didn't see any, but it was fun to be close.

On two consecutive days we took eight- hour hikes that were rigorous but doable for anyone in reasonably good physical condition. And while the nights were cold, our tents were sufficiently insulated and our bodies tired enough to make sleeping easy and deep. During the days we packed picnic lunches and at night we ate soups and stews with other hikers at our base camp. Our morning alarm was the smell of hot cereal cooking over an open fire.

From the distance of our camping site, the 10,000-foot Mount Fitz Roy and the range of peaks surrounding it looked like a great cathedral covered by snow. But as we got closer, forging glacial streams over planks of wood and walking over the huge moraines, rock piles strewn about by surging glaciers centuries ago, Mount Fitz Roy and Cerro Torre became more imposing, even forbidding. I had no intention of climbing either one of them.

The two-hour climb up a series of steep moraines to the De Los Tres lagoon, at the base of -and 6,000 feet below- Fitz Roy, was thrilling enough. At times we were on all fours to keep from falling. Once we reached the top of the last moraine, the winds sweeping across the bright blue lagoon were wicked. They created large whitecaps on the water and forced us to seek shelter behind rocks. I felt the piercing cold in my bones and my teeth rattled.

The three of us quickly found a sheltered ridge, overlooking Sucia Lagoon and the Río Blanco glacier, and ate some carrot salad before a spectacular view. The winds died down enough for us to see Fitz Roy in all its glory. Clouds whipped through the massif in a powerful swirl that explained why the Tehuelche Indians originally named the granite spike Chaltén, or peak of fire, in the mistaken belief that it was a volcano.

The hike down was easier, and the view of the surrounding mountains and Viedma Lake magnificent. I picked a Calafate plant to eat its fruit. I wasn't particularly hungry, but I knew the old Indian fable that a taste of the Calafate assures a return visit.