Buchaille Etive Mor, the “Big Shepherd” of Rannoch Moor will never have seen a gathering quite like it. At 1.00pm today, 37 women, aged been 35 and 92, many with their exhausted male partners in tow, will gather at the summit, 3,352ft above sea level. Some will be dressed in Edwardian skirts and knickerbockers; a few will be a little out of breath. But all will join in a rousing chorus of Happy Birthday.

Such is the centenary celebration planned for the Ladies Scottish Climbing Club, a unique institution founded in the heat of Suffragettism and still going strong. From its inception, the “Ladies Scottish” challenged the male establishment, set records and sent its members off to tackle some of the toughest climbs in the world.

The club produced the first female Munroist, Annie Hirst, and in Kathy Murgatroyd has the first woman to complete all 284 Munros (peaks in of 3,000ft or more) in an unbroken chain, travelling between them on foot or by bike.

In 1955, members of the Ladies Scottish formed the first women-only expedition to the Himalayas. One of the veterans of that extraordinary trek, Evelyn Nichol (nee Camrass) will be on Buchaille Etive Mor today, her friends say, but only “if she gets back from Thailand in time”.

But while it may be plain that the Ladies Scottish is more than just a book club with altitude, its members insist that they are nothing out of the ordinary. “There are women who cycle, or run or play hockey - I don't think we are any different, this just happens to be our hobby,” says Alison Higham, 60, a retired teacher from Kirkintilloch.

“Most women enjoy getting out into the countryside, away from the stress of work or town or driving, and they enjoy the companionship. Some walk, some climb. Older members just enjoy being out there. The important thing is the companionship.”

Many of the women say a single-sex club allows them to develop at their own pace, and, unlike mixed clubs, offers them the chance to lead. Karin Froebel, 58, is an accomplished climber who will ascend today by Agag's Groove, one of the Highland's classic rock walls. A former research immunologist specialising in HIV, she believes that mountain craft brings with it a sense of achievement which transfers into every aspect of life.

“I enjoy mixed climbing clubs, but the women's only side is important,” she says. “It's not necessarily better but its different. I know that I could not have done what I have done in leadership terms without this.”

The club's ideal were founded in the Edwardian era by Jane Inglis Clarke, her daughter Mabel, and Lucy Smith whose husbands and fathers were members of the Scottish Mountaineering Club. Ladies were barred from the SMC - so they founded their own.

At first membership was the preserve of the upper crust, who had the leisure to take advantage of the Highlands. But gradually it widened, and the notion that sisters could do it for themselves persisted.

In the 1970s, as the women's movement grew, the Ladies Scottish acquired a new impetus. “It was a time of women branching out, burning their bras. It was attractive to me,” says Mrs Higham, 60, who has often climbed with her husband, but found that a women's club offered a new dimension.

“I used to climb with my husband, usually in a ‘second' capacity. But I got as much fun leading at a lower grade. It's not that we are anti-men, but women can find their own level, without the pressure of a mixed group.”

The spirit of adventure established by the club's pioneers is alive and well among the 115 members. On Sunday, club president, Helen Steven, 65, will lead a three-week trek along a 112-mile (180km) route between Glencoe and Dundonell. And in July, 20 women are heading to Bolivia to tackle Pequeno Alpamayo, a daunting 17,552ft glacial peak. Mrs Nicholl, an octogenarian hopes to make the trip.

Younger women are welcome too, but don't always want to join. Mrs Froebel says that in her twenties she too was reluctant. “At that time I was looking for a partner, that was part of the agenda.

“But a ladies club is simply about what you are doing on the hill. Ultimately that is the attraction.”

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