My world has turned into a cocoon of fibers — fleece, wool, a feather quilt — and it nudges me into gentle slumber. I drift while watching a pure, starry galaxy fill my tent’s rooftop window. Conditions appear brisk, but calm. The landscape seems stark, yet stunning. Good sleeping weather, I decide.

So it is a jolt when the surreal howling — like a train whistle, only more demonic — arrives in the wee hours with thrashes and slaps to the sides of my roost. It is annoying in sound, alarming in persistence, unnerving in its potency.

Untying the tent flaps would be ludicrous, so there will be no confrontation with this beast. I am amazed and befuddled; I consider groping for earplugs. Then the rude interruption disappears almost as abruptly as it arrived.

At breakfast, our guide merely shrugs. It was the wind. Nothing extraordinary, he says. Maybe 35 mph, tops. Gusts of four times that speed have been recorded.

This is Patagonia, at the bottom of Chile and Argentina, near the end of the world. The wind is in charge, and we all will learn this long before our stay ends. “Nature is outside, knocking at the door,” our eco-camp guides tell us.

We are reminded of the wind’s power again and again during the next three days. Gales will unbalance hikers as we round a bend, reach a summit, board a rubber dinghy and slosh closer to stunning, icy-blue glaciers. Currents seem to surge from nowhere to whip our cheeks, kick sand into our eyes, challenge our equilibrium and rock us toward motion sickness.

The wind invigorates, shocks and enthralls, although most appearances seem brief during this visit. When the wind sleeps or whispers, what remains is exquisite beauty and — to borrow a phrase from Philippians — a peace that passes all understanding.

Our base is an eco-camp set inside the 450,000-acre Torres del Paine National Park, which since 1978 has been a UNESCO world biosphere reserve. It is considered one of the most uncontaminated places on the planet, lush with waterfalls, glaciers, lakes and mountainous terrain.

The occasional gaucho hovers along hilly ridges, checking the whereabouts of sheep that wander onto park property. Rheas strut leisurely along miles of uninterrupted, uncluttered acreage. Herds of wild guanaco — similar to the alpaca, but with softer fur — roam, scuffle and butt heads to determine dominance. The main predator of all is the puma, which seems to make itself scarce until hungry.

Andean condors, with their 10-foot wingspans, and buzzard eagles soar and swoop, in search of a convenient lunch. The daintier black-necked swan and spectacled duck prefer to hunt in water.

“It is just the appetizer,” guide Armando Iglesias tells us, as we stand in awe at the end of our first short hike, to Salto Grande waterfall. He used to work as a gaucho with his father; they cared for 4,800 sheep and 20 cattle on 5,000 acres of Patagonia’s Tierra del Fuego. The rule of thumb is one grazing animal per acre, to avoid ruining the nutrient-challenged land.

All of our guides are government-certified, which is proof of knowledge about the park and its terrain, inhabitants, moods — plus how to prevent, confront and survive life-threatening predicaments.

Guide Cristian Silva talks about carrying on his back a hiker who broke an ankle during a 12-mile roundtrip trek to the foot of Paine Towers, the park’s most common hike. It is a full-day adventure, following many hills and valleys before attempting a rock scramble to the trail’s summit.

Participation requires physical fitness, and those who succeed can consider the five-day “W” hike that involves camping and carrying more gear. There are easy hikes, too, at least by Patagonia standards: I know of few who would use poles during a 5-mile hike termed “easy” in the U.S. Midwest, where I live, then end the day negotiating a steep scree of loose sand and sedimentary rubble.

In December, when the northern United States struggles with windchill and snowfal l, it is full-throttle summer in Patagonia, a tremendously remote and idyllic part of the world. Even though Torres del Paine is open all year, it is best to visit the park from October to April — the southern hemisphere’s spring to summer.

Prepare for all moods of weather, but come with an open mind. There is a lot that I wouldn’t have believed about Patagonia until seeing and feeling it.

My fears of wind-burned cheeks and chapped lips were more unwarranted than the risk of sunburn. Packing a winter parka isn’t as practical as wearing layers of clothing with zippers, to react quickly — and repeatedly — to abrupt changes in wind or a sudden onset of precipitation. “Wear a hat that stays on” is good and necessary advice.

Our eco-camp, which began as a rafting and kayaking company, is far from rustic. A pot-bellied stove toasts the interior of a domed tent 30 feet in diameter and 13.5 feet tall (see photo below), used for meals and socializing. A large window of heavy plastic faces the looming Paine Towers.

Slow-roasted lamb (a traditional Patagonian barbecue) and broiled salmon with capers are served on linen-clad tables, accompanied by goblets of fine Chilean wines. For happy hour: pisco sours, the national drink of Chile. The drink is a sweet liqueur mixed with egg whites and lime juice.

Although the eco-camp — which has been open since 2001 — is described as having “the comfort and sophistication of a 4-star hotel,” not all of the traditional U.S. amenities are duplicated. Eco-sensitivity matters more than customer pampering.

We are truly unplugged from the rest of the world: no phones, television, radio or Internet connections. The electricity that is generated is not wasted on hairdryers. We reuse our plastic water bottles, over and over.

There is room for 30 travelers, and single-occupancy tent accommodations are rare. Inside each tent (see photo above) are two thick but narrow mattresses and an animal skin rug. Sunrays, through rooftop windows and opened flaps, naturally heat these cozy bedrooms during daylight hours.

Tent temperature at night is about 40 degrees. During daytime, it is often sunny and in the 70s, but spurts of rain come and go. The sound of thunder can be misleading; it accompanies ice avalanches as well as rain.

It is a short shuffle to the composting toilet and showers, via raised wooden platforms, to lessen environmental disruption. Hydroelectricity and solar power generate energy for light, heat and water in showers. Ironically perhaps, the use of wind energy here has been problematic; wind levels are unpredictable and wind turbines are noisy.

Getting to camp means riding in a van that crawls onto a one-lane bridge during the last leg of travel, with only inches to spare on either side of the vehicle. The bridge was built for cattle drives before the area became a national park, and so far there has been no need to make it wider.

Park roads are dirt and gravel. It is not the place to take a rental car. Most of the vehicles that transport us have at least one nasty windshield crack.

The domed tents come down in April, as the ravages of winter approach, and this camp is not the only lodging option at the park. A handful of hosterias — simple but clean lodges — also exist. Costs depend on length of stay, time of year and type of itinerary.

Our guides are torn between wanting to share what they love, and knowing that the presence of more humans could destroy their paradise.

“The park already has too many people,” Cristian asserts. This is a matter of perspective; during our four days of adventure, it was rare to encounter other people and vehicles. But at the peak of summer, hikers sometimes will have to wait on trails for people heading in the opposite direction to pass. There are not many hiking trails, and some are not easily accessible.

Before our visit ends, we meet John Garner, an adventurer and former park employee who helped create the Torres del Paine road and hiking circuits. He is a longtime mountain and ice cap climber, who once was buried under snow for 10 days during his explorations.

Within 30 miles of our base camp, Garner says, “there are places that remain untroubled, and that is why I keep coming back. It is the anticipation that often makes the journey.”

It is the same way for nature lovers who are appreciative but not as brave.

INFO TO GO

This journey begins with an overnight in Santiago, then a four-hour flight south to Punta Arenas, on the Strait of Magellan. From there, it is a three-hour drive southwest, for a meal at Puerto Natales, population 17,000, then another 2.5 hours on the road to Torres del Paine National Park, and a bumpy 15-minute ride from the park’s Laguna Amarga entrance to reach the Cascada Expediciones EcoCamp (tel 800 901 6987).

The cost for a four-day, lower-impact visit to the Cascada EcoCamp is about $900, which includes transportation from/to Punta Arenas. It’s $1,675 for a more intensive, seven-day trekking adventure. Prices do not include guide gratuity.