Sexagenerian mountaineer Reinhold Messner is to return to Nepal to tackle a "new" mountain - but will be upholding a pledge never to return to Everest.

After seeking permission from the Nepali government for the past decade, the 62-year-old Italian climber has finally being given the go ahead to be the first western climber to tackle the mountain. All visitors must have permits to climb - but Messner is refusing to reveal which mountain it is.

"It is an unknown mountain and I won't tell you which it is - then there will be lots of people there," he told Times Online. "I will be going there in spring 2008, then afterwards I am going back to Patagonia to cross an ice field. I still climb a little but always go on an expedition once a year."

The indefatigable climber twice conquered Everest, in 1978 (without supplementary oxygen) and in 1980, and was the first to climb all 14 mountains higher than 8,000 metres - but he has no interest in returning to the world's highest mountain.

"I was last there in 2003 and it took me two hours to walk across base camp. There's even an internet cafe on the south side," he says. "Mountaineering begins where tourism ends and what you see on Everest today is typical tourism. Last spring there were 500 people waiting to go to the top in one day.

"It is like London in the rush hour. Everest is not a mountain any more, it's not even a hill. It's a highway - I wouldn't go up Everest again if you paid me. I go where tourists don't go"

Speaking in London this week, Messner revealed plans for his fifth and final mountain museum in South Tyrol, the northernmost province of Italy that is his home.

Describing himself as "a climber at the end of his life," he said the fifth museum - to be housed in a donated castle - will be devoted to mountain people. South Tyrol depends on "high-class tourism," said Messner, and each of the musems, which attract 100,000 visitors a year, are devoted to different aspects of mountaineering as opposed to artefacts. "Mountaineering is only 230 years old and that history is not strong enough to fill a room," he says.

His fourth museum, the Messner Mountain Museum Firmian at Castle Sigmondskron, overlooking Bolzano, opened last spring with mountain mysticsm to the fore: the religions, music, folkore, art and culture of mountains are represented in a "meeting point for man and mountain," said Messner.

"At the age of 50-55, I learned to give back what I learned on the mountain. It is about people, the sherpas. I learned from them how to survive on a mountain so this is not really about opening museums, it is a place of encounter. I use the quote from William Blake: 'Where men and mountains meet, big things are happening.'"

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