for glory of completing `earth's last great land journey' on earth'

On a 35-day expedition in Antarctica last year, Mear experimented with a kite or "para-wing" to speed his travel on windier days. Without it, he reckons the journey would take at least another 20 days. Ousland will harness himself to a similar device, and in keeping with his natural approach, he will wear only wool and cotton clothing.

Apart from the crevasses, Mear's other big worry is sponsorship. He estimates the total cost of the expedition as pounds 250,000, of which pounds 127,000 is the inescapable cost of the flight from Punta Arenas in Chile to Patriot Hills in Antarctica and on by ski-equipped Twin Otter to Berkner Island by the Weddell Sea. So far, he has raised pounds 50,000, and has also gained considerable support from Sainsbury's whose nutritional expertise has helped produce a perfectly balanced diet to give him the 5,300 calories a day he needs.

Ousland is in a much more comfortable position, having secured a main sponsor in an Italian sports watch company, Sector.

The Norwegian has also crossed the loneliness barrier. Last year, he became the first person to ski alone and unsupported to the North Pole - a 52-day trek over 620 miles from Cape Arctichesky in Siberia.

"People are very afraid of being alone," says Ousland. "But I discovered on the North Pole that being alone was one of the greatest things of the whole expedition. I got much closer to myself and to nature. It isn't so scary, but for three months alone you need to be in harmony with yourself before you go, otherwise you are doomed."

Mear admits he just does not know how he will cope with being alone, but he does not seem to have any big hang ups about it. Unlike Ousland, he knows Antarctica and has skied the route to the Pole.

On the muscular side of wiry, he keeps in trim running along the gritstone edges near his Peak District home and weight training. He also has an impressive mountaineering record - the North Face of the Eiger in winter 15 years ago, the first British ascent of Nanga Parbat in the Himalayas, and bold attempts on Everest and K2. He has also climbed Mount Vinson, the highest peak in Antarctica.

Perhaps the key though is his undiminished love of the continent. It will be his fifth visit. "There is obviously physical hardship, but I go out to minimise that and make myself as efficient and comfortable as possible.

"All you ever hear about with the Antarctic is heroic deaths, failures and frostbite, but it's not like that. It is one of the few places on earth where you can stand and think this is a timeless landscape, virtually untouched by mankind.

"Running on skis though this, or settling down in your sleeping bag with a mug of tea and the snow singing outside the tent, it's simply wonderful."