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K2, the world's second highest mountain, was first climbed by Italians Lino Lacedelli and Achille Compagnon (all pictures courtesy of K2 2004 - 50 years later).

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They reached the summit at 1800 hours (local time) on 31 July, 1954.

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Since the first ascent, there have been around 190 similar conquests, and around 50 deaths. Most climbers have died on the way down.

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Mountaineers from all over the world are celebrating the anniversary, including Mr Compagnoni's nephew, who was among two groups who climbed K2 this month - the first successful ascents in three years.

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In the far north of Pakistan, K2 was and remains barely visible from any inhabited place. In 1954 conditions were hazardous most of the time.

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Despite improvements in technology, the mountain is today as dangerous as it was then with a much higher rate of fatalities than Everest.

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After the first ascent of K2, mountaineering became an important part of Pakistan's tourism industry.

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K2 has claimed the lives of three South Korean climbers and five Pakistani porters so far this year.

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To mark the anniversary fees for climbing K2 have been cut in half to $6,000 per team.

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A mountaineering museum is being built not far from Skardu near K2, where an exhibition marking the jubilee will be held.