The approach to base camp is the same as for Broad Peak and the Gasherbrums. The treks starts from Skardu and ends at Concordia. From Concordia it takes a few ours trek to K2 Base Camp.
This route was described to me by a Dutch Climber a couple of years back. I, personally have not attempted this route or for that matter K2 itself.
This route was first climbed by the Italians in 1954 and is considered to be the normal route on K2. The route is extremely difficult and dangerous involving a steep ascent on loose scree for almost a kilometer. The most difficult challenge on way to Camp 1 is the danger of falling rocks from Camp 1 and beyond.
CAMP 1 (6000m)
C1 is on an exposed bit of patch but is considered to be relatively secure, with little or no history of avalanches. One the way up to Camp 2 one has to navigate over the famous “House Chimney” which is a 50-meter wide crack. People who have seen it describe it as a spider’s web of old ropes. One Polish climber jokingly told me that these ropes if put together in length, would be enough to run around the base of the entire mountain itself.
CAMP 2 (6700m)
Camp 2 is usually set up under a large rock on the shoulder, but the place can get extremely windy and cold. The climb up to camp 3 is probably the most technical and difficult. On the way, one comes across the infamous “Black Pyramid”, which is a mix of rock and ice with near vertical climbing.
CAMP 3 (7250m)
Camp three is perched on the top of the Black Pyramid. Unusually, this is a more horizontal bit of terrain, comprising mostly of snow fields ranging from 25 to 40 degree slopes. At this height, during unsettled weather conditions (which is the case most of the time at K2) the gap between K2 and Broad Peak acts as a narrow window (narrow in relative terms) creating a funnel effect, with high speed winds gushing out between the two peaks. This phenomena makes this area extremely prone to avalanches.
The run up from Camp 3 to Camp 4 is usually a fast toil through seemingly endless snow fields normally without fixed lines. In addition to the extreme avalanche conditions due to high winds, there have been many reports of entire sections of the shoulder itself cracking and falling off triggering huge avalanches.
CAMP 4 (7500m – 8000m)
There is no fixed spot or altitude for camp 4. Weather conditions dictate the choice of these two. From this point the summit bid can take anywhere between 12 hours to 24 hours, depending on the altitude of Camp 4 and weather conditions.
With the summit within sight, the biggest challenge is still to overcome. To reach the summit, climbers have to climb a near vertical narrow coulloir infamously known as the “Bottleneck” which goes on for about a 100 meters. At a height of 8300m, strong winds and the cold create the most challenging and dangerous climbing conditions requiring concentration and determination, which, even seasoned climbers find difficult to muster. One may also encounter live ice (extremely slippery where even crampons cannot provide solid footing) during cold and wind swept conditions.
One should be fully equipped. Most climbers advise to travel light from Camp 3 onwards as extreme and quick weather changes can force hasty retreats.
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