Great pool. Which is nice when ...

Llamas. Not the kind of creature one expects to see by the pool of a luxury hotel. There it was, grinning slightly salaciously, I thought, as I headed for a twilight swim. But then Explora, a luxury lodge in Chile's Atacama Desert, is not your average hotel. And voyeuristic llamas aside, there is nothing like doing al fresco backstroke to get rid of hours of planes, pains and bumpy automobiles.

Llamas. Not the kind of creature one expects to see by the pool of a luxury hotel. There it was, grinning slightly salaciously, I thought, as I headed for a twilight swim. But then Explora, a luxury lodge in Chile's Atacama Desert, is not your average hotel. And voyeuristic llamas aside, there is nothing like doing al fresco backstroke to get rid of hours of planes, pains and bumpy automobiles.

Faced with a few days' trekking in one of the world's wildest terrains, it made sense to limber up. It was a long way to come for a walk but in Chile the best bits are saved until last. From its southernmost ice caps to northernmost desert, Chile is a country of extremes. Not least in that you have to travel an extremely long way to get to it. And then even further to get to the parts that make it one of the adventure capitals of the world.

There are two Explora lodges in Chile - the one I stayed in, at the northern end of the country, the other in the far south. Luxury eco-lodges, they cater for well-heeled adventurers who will travel across the globe to get their wilderness kicks providing there's a comfy bed at the end of it. Pedro Ibanez Santa Maria, the owner, sees it more subtly. "He abhors the word luxury in the traditional sense," explains the hotel manager, Paul Rodwell. "Dom Pedro prefers the surroundings to speak for themselves. Explora provides the simple things: privacy, clean water, peace and quiet. Everything here is very real."

It is a certain calibre of "simple things" that brings Explora its somewhat starry clientele. The place is a favourite with the kind of celebs who fall for daily adventure tours planned for them each night over a fireside pisco sour. And with those who love the less-is-more ethos employed in the hotel's decor and architecture. Simple wicker furniture and tapestries crafted by local artisans contrast just-so with imported linen and china. As part of Dom Pedro's "keeping it real" atmosphere, most staff members speak not-so-perfect English and the service is pleasantly laid back. What they are fluent in, it quickly becomes clear, is expedition-style back-up. Within hours of arrival, one of our party is already flagging because of altitude sickness, and someone is immediately on hand with a hi-tech oxygen cylinder and curative cocoa tea.

Explora is located in San Pedro de Atacama, an oasis town in one of the driest places on Earth, an "absolute desert" where rainfall is rarely recorded. Add to this an altitude of 2,443 metres above sea level and you have some pretty challenging terrain for outdoor pursuits. It's hard to tell, however, who will find the going toughest. Altitude sickness, true to its arbitrary nature, struck the youngest and, in theory, fittest member of our party while the oldest was gamely knocking back the Chilean red over dinner. What is guaranteed is that any kind of sightseeing efforts will be magnificently rewarded. Visibility in this part of the world is remarkable. The snow-capped peaks of the region's numerous volcanoes, some 190km away, seem within grasping distance of our bedroom windows. And with clear skies and zero artificial light even in the dark the view is spectacular.

We set off the next morning after first light. The lodge offers numerous excursions, from volcano climbs with overnight camping to a leisurely horse ride through The Valley of the Death, a desert canyon of sandy pink rock over which a shepherd was said to have driven his sheep after seeing the Devil. We choose something rather more celestial - a trek through the Altiplano, the high Andean plains, climbing 4,000 metres above sea level. Following shepherds' trails, we hop over semi-frozen trickles of river using bouncy yellow patches of "mother-in-law's cushion" cactus as stepping stones. It's June - winter - and around 22C. Out of the sharp sunlight it feels more like -22C.

Between patches of pampas, crumbling dry-stone corals can be seen along with the skeletal remains of a shepherd's pirca, an overnight shelter made of sticks and llama skins. Our guide, Ayela, points out patches of terraced land where garlic, onion and quinoa (an Andean grain) would have been grown. From under her wraparound shades, she nods towards a patch of copa copa plant, explaining its dual use as stomach settler and ritual incense. We exchange a few words about Pacha Mama, the mother earth to which locals make reverent offerings. A cool nod of approval for the Colombian hemp bag I am carrying signals that our short conversation is over, and then all is quiet again.

The following day brings the same desolate calm with a walk through Valley de la Luna. This 6km gorge, created by eroding salt mountains, is the favoured spot for sunrise or sunset hikes. It's a wonder anything survives here, not least the rare James's flamingoes that reside on the Atacama's salt lakes. Violently oscillating temperatures (daytime highs of 46C, to nightly lows of -20C) often see the birds frozen where they roost, the dawn sun bringing a thaw and liberation.

The curious thing about deserts is that as soon as there is less we want to know more. With civilisation and vegetation beaten back, the Earth's skeletal crust revealed, an obsession develops with the great "hows" and "whys" of our planet's natural make-up. Plate tectonics, the movements of the sun, the creation of volcanoes; these all become the stuff of daily consideration. It's no surprise that Explora is in the process of building an observatory. In its absence, our guide does an impressive job of answering the kind of astronomical questions usually asked by an encyclopaedia-clutching child.

After several days of legwork, we take a final short hike out of San Pedro's dusty environs to discover Puritama hot springs. This series of geothermal pools constitutes San Pedro's leisure centre. Local children splash around in the bath-like water - an antidote to a life of sand and dust.

Explora's investment helped to clean up the springs, giving the community safe walkways, changing huts and, for hotel guests, a pool of their own to loll around in. A hotel Jeep greets us with a trunk load of fluffy white robes and picnic hampers. No sooner have we submerged sore limbs than trays of hors d'oeuvres and glasses of wine are floated to us across the water. As ever, for Explora guests the simple things in life come in a very particular way.

GIVE ME THE FACTS

How to get there

Sarah Barrell travelled as a guest of Varig Airlines (020-8321 7170; www.varig.co.uk). Flights from Heathrow to Santiago start from around £665 return via Sao Paulo or Rio de Janeiro.

Where to stay

Three nights' full-board accommodation at the Explora Hotel, Atacama (00 56 2206 6060; www.explora.com) costs from £910 per person, based on two sharing, including transfers and activities. Travellers usually have to spend one night at either end in the Chilean capital, Santiago. Travel Art (00 56 2378 3440; www.travelart.com) is a local tour operator that can arrange excursions, hotels and provide general advice for travel in Santiago and throughout Chile.

Further information

For a free guide to Latin America, contact Lata, the Latin American Travel Association (020-8715 2913; www.lata.org).