Descending through the dense, dark banks of snow-clouds covering Patagonia – after an 18-hour flight from London, an overnight stay in Santiago, then a four-hour flight to the end-of-the-earth town of Punta Arenas – I began to wonder why my partner, Lloyd, and I had committed ourselves to two weeks in Chile in July.
It was the southern hemisphere's winter and we were about to land near the Antarctic, in a place that even the optimist Charles Darwin called "arid wastes described only by negative characters: without habitations, without water, without mountains".
At the small, snow-covered airport of Punta Arenas, there was little to dispel our bleak moods. Dense mist swirled damply on our skin. We drove off, past the black silhouettes of leafless trees. Banks of snow scooped up by ploughs lay grey beside the road; ice glimmered in the yellow half-light.
Over five long hours, the golden pampas grasslands of Chile appeared, then vanished, eerily glowing in dusky light. By the time we got to our destination, a long, split-level building that looked like a white cruise liner about to sail out of the black hillside, our burnt-out city nerves were fizzing.
But the next morning, waking before dawn, I got up to peek behind a blind – and let out a screech of happiness. Soaring into fierce red dawn skies were the Tolkienesque peaks of the Torres del Paine mountains: 10,000ft granite obelisks sculpted into jagged shapes by millennia of ice, wind and rain.
Opening the window, I could hear a waterfall thundering over rocks nearby. And in the still waters of Lake Pehoé below the hotel, a mirror-image of the mountains shimmered in the soft light: brilliant pinks, purples and blues that heralded the start of a perfect winter's day. The clouds had gone. Our cosy room was flooded with warm, pink light. And we were in the middle of nowhere: at the bottom of South America, looking out over one of the most beautiful scenes on Earth.
In the Torres del Paine National Park, an area of more than half a million acres, it's not just moods that can change overnight. "You can have four seasons in a day, from hot summer to freezing winter," our fresh-faced guide, Juan Munznayer, told us after breakfast. "So you need to layer up like an onion."
The point of staying at an Explora hotel isn't to mooch about indoors, taking advantage of the all-inclusive rates. It's to take part in activities. "To us, luxury is enabling people to experience the real pleasures of life in very remote places," the motherly manager, Rosaria, told us.
Which explains the odd architecture of the building: long, so every room has views of the mountains; low, for energy efficiency; and minimally decorated so visitors can focus on the ever-changing scenery.
Having discussed with our guide, Juan, the options for activities – about five are offered every day – we set out a tentative plan for our three-day stay, and an opt-out clause if we felt more inclined to head to the indoor pool and sauna down by the lake or the four heated Jacuzzis on decks overlooking the mountains.
Once we got into the snowy air and started to enjoy the physicality of the mountains, we soon realised there would be no opting out. All day we had to keep stopping to take in the views over hundreds of miles of wintry landscape: lakes thick with ice, glimmering in the sun; ancient valleys, 20 miles wide, once carved by glaciers and now covered in golden pampas grass; rivers thick with ice drifting through rocky ravines; waterfalls frozen in air.
We assumed we would never see a puma, so when we came across great pawprints in the snow I took a few snaps. But just as we were hiking out of a valley, one of the guests spotted something perched on a rock, looking down at us. "Ohmygod!" the guide grinned. "I've only ever seen ten in my entire life. It's a puma!"
And there it was: South America's famous big cat, light-marmalade fur lining its back, white fur adorning its chest and stomach, a small, tan head, and a tail thick and furiously flicking.
Celebrating our sighting back in the lodge, in front of fires with hot smoked almonds and pisco sours, we were convinced that the days couldn't get better. But they could.
Patagonia is a place that seduces strangers slowly; the longer we stayed, the more besotted we became. On our second morning we hiked up to a lookout point below the great towers of the mountain range, and for an hour just gazed up, mesmerised by the 6,900ft "horns" of the Paine massif.
We embarked on a six-hour walk to the French Glacier, and listened to the rumble of avalanches while watching house-sized pieces of ice tumble off, smashing on to rocks and then pouring down the mountain as showers of white powder. And every day we relished the treat of being able to stroll silently amid mountains, water and sky, with no one else in sight (an unlikely occurrence in summer, apparently, when the park has more than 150,000 visitors). While the scenery is spectacular, what makes it extra-special is the sense of isolation it engenders.
Later, in Explora's stables, a gaucho saddled up three glossy-coated thoroughbreds and, in the afternoon light, we took to the plains: tearing across grasslands, wading through pebble-lined rivers, quietly watching eagles soar overhead. At sunset, we drank yerba mate tea shared from a gourd, the gauchos bunched around a wood-burning stove in their traditional woollen plus-fours, soft leather boots, berets and ponchos.
If we had had another day or two, I would have returned to join them again and again: to hear more stories of their cattle-herding across thousands of miles of plains, of their battles with pumas, of families abandoned while they searched for new pastures.
But it was our last night. So instead we scurried in the freezing air to the pool house by the lake, poured ourselves some fruity merlot, and, beneath the moon and a dazzle of stars, let the warm bubbling waters of the Jacuzzi thaw us out.
By Lisa Grainger, Telegraph Journalist