El Chalten After four weeks of culture, sights and beach, the real adventure begins. For someone who only bought her first pair of hiking boots a month ago, a two-week expedition is a slightly daunting prospect. I book a trek with Intrepid Travel which takes in the prime trekking country of the Patagonia region in Argentina and Chile's south.

I meet the group in Buenos Aires. Our tour guide is Ana, a lively and very well-informed Argentinian chica from Mendoza, Argentina's famous wine-growing region - we quickly discover that she handily doubles up as a sommellier at meal times. The group is an eclectic bunch, including a newly-wed Aussie couple, a hilarious doctor from south London and a charming photography-mad professor from Arkansas. I have no idea whether it's a rarity to like everyone in a group of 13, but it proved to be a very lucky number for our trek.

We fly over two thousand kilometres south to El Calafate, a three-and-a-half hour plane ride away in southern Argentina's Santa Cruz Province. El Calafate is the main hub for one of southern Patagonia's (and Argentina's) key highlights - the Perito Moreno glacier, one of the world's few advancing glaciers by occupying more land as it moves forward along the L-shaped Lago Argentino in Parque National Los Glaciares (a UNESCO World Heritage Site national park). It really is a sight to behold, a meringue-like ice formation of over 250km(squared), 30km long and up to 60km high. We stand mesmerised and listen out for explosions of ice - if you look across the lake, you can see huge floating chunks of ice. The boat ride along the glacier allows you to see up close and personal, but by far the most impressive sight is from the many viewpoints where you're overwhelmed by its size and magnificence.

Perito Mereno Easing us into our first day was no bad idea but now the serious walking begins and to see such beauty, we have to work for it. We travel over 200 kilometres to the pretty, laidback hiking town of El Chalten, also in the Parque National Los Glaciares, and home to the beautiful granite masif of Fitz Roy Mountain (Cerro Fitz Roy), 3405 metres above sea level and Cerro Torre Mountain, 3102 metres above sea level. The first day is a 25-kilometre round trip and as the least experienced walker, I can comfortably admit that I had never walked for so long or so far in all my life. Passing blue glaciers and gorgeous lakes makes it a little easier and the final vista of and Fitz Roy, although somewhat clouded, is incredible. We are all armed with plenty of snacks, causing our guide David to comment that everytime we stop, someone is always eating.

The evenings are reminiscent of ski holidays. After a day in the mountains, all you want is a hot shower, a glass of something and lots of food. Ana knows her destinations well and we dine fabulously each night on succulent steak, delicious Patagonian lamb, homemade pasta and of course, a cheeky glass or two of Argentinian red.

I brace myself for what's to come. We are about to leave Argentinian Patagonia for Chilean Patagonia and the hardest hike of all - the climb up to see the Torres del Paine in the national park of the same name. I stock up on cereal bars, catch up on sleep and hope for the best!

The writer is travelling courtesy of www.ebookers.com a leading pan-European online travel agency. The Patagonian Wilderness trek is hosted by Intrepid Travel who specialise in small group adventures throughout Europe, Asia, Africa, the Middle East, Latin America, Australasia and the Pacific.