Today marks 100 years since the first ascent of Mt Aspiring, New Zealand's highest peak outside the Aoraki-Mt Cook region.

Around 1pm on November 23, 1909, guides Jack Clarke and Alec Graham and their client Bernard Head stepped on to the 3027m summit, where they spent five, freezing minutes.

Clarke was a former chief guide at Mt Cook and was among the three-strong group to make the first ascent of Cook on Christmas Day in 1894.

The Aspiring trio chopped steps with their long-handled ice-axes up the West Face, a steep route subsequently climbed only rarely on the mountain known as the Matterhorn of the South.

Their expedition, which began in the Lake Wanaka area, took around a fortnight.

Nowadays, a fit walking party might do the return trip in three days from the road-end; mountaineers who pay for helicopter flights to the summer snow-line might take two.

"It's in the period where they were still having to explore to find the mountain," says historian Graham Langton, of Wellington, whose article on the expedition will be published in the New Zealand Alpine Journal next month.

"They had a look up the East Matukituki River first. There's no access that way.

"They went back to the East/West Matukituki junction and with help from the runholder and his packhorses, went up the West Matukituki."

They travelled to the head of this river but could not see their prize, hidden behind steep foreground slopes and the Bonar Glacier.

Eventually they found their way on to French Ridge and camped at its head before climbing the West Face.

"When you look at the West Face today you think, 'What were they doing there with no crampons'."

But Mr Langton said the Bonar Glacier had shrunk and the face was probably much steeper than it was in 1909.

Theirs was the first attempt to climb Aspiring (Tititea). Mr Graham had been on a previous expedition towards the mountain, from South Westland's Waiatoto River.

"They would have liked to have a go, but by the time they got up the valley, they didn't have time for a serious attempt."

The alpine club is running a photo competition to mark the centenary and the winning entries will feature in a centenary celebration at Wanaka on Saturday.