Cordillera Vilcanota, Colque Cruz Range, Various Ascents, and Research on the affect of altitude and acclimatization on basic neurophysical and cognitive function and erectile function. After looking carefully at the Alpine and American Alpine Journals, we (Simon Cooke, Leader; James Hall, Gordon Midgley, Phil Bent, Nick Wallis) realized that the south side of the Colque Cruz peaks had never been visited, and that Chumpe/Jatunriti (6106 m) had only been climbed from the south, in 1955. The superb west face of Jatunhuma II (5800 m) was unclimbed and the summit not visited by a British team.

The walk to Base Camp (4600 m) near the Laguna Mullucocha took a day with nine horses and three arreros (£40). The next four days were spent on short walks up to 5120 meters and some excellent multi-pitch rock climbing to UIAA VI. On August 4, Nick and Phil made an attempt on the Horrorhorn (5852 m) from a col to the southwest, getting to 5400 meters before turning back due to acclimatization and snow problems. On August 5, Simon and Cordon made an ascent of Pata Anata (P.5400m, to the north of Cayangate IV, 6085 m) via 60-degree snow on the north face. We could not find reference to this peak having been climbed before. On August 6, Phil, Gordon and Nick made an attempt on the north face of Cayangate IV (6085 m). They turned back at 5400 meters due to acclimatization problems. Simon, accompanied by James, made a rapid descent back to Base Camp with suspected cerebral edema.

We spent the next five days bouldering and rock climbing then established and stocked an Advanced Base Camp at 5100 meters on the long approach to Chumpe/Jatunriti. On August 11 we made a bivy at 5600 meters on a glacial shelf between Chumpe/Jatunriti (6106 m) and Colque Cruz VI (5930 m). On the 12th, Simon, Gordon, Phil and Nick made the second ascent (the first since 1955) of Chumpe/Jatunriti, initially (300 meters) on 50 to 80-degree ice, then via a broad ridge. We were stopped at 6085 meters by an enormous crevasse/serac (including a four- meter horizontal overhang). The next day was spent removing all the tents from the mountain and returning to Base Camp, where bad weather pinned us for four days, preventing any further activity. On August 17, we started our return to Cusco.

Analysis of the cognitive and basic neurophysical tests is being undertaken by the Department of Psychology, University of Sheffield. Use of expansion tapes showed that 80% of the expedition members continued to get nightly nocturnal tumescences up to 5600 meters.

Jatunhuma II and the south faces of the Colque Cruz range were not attempted by our expedition and there remains great scope for new routes up 50- to 80-degree ice and mixed terrain. The position and sizes of the glaciers and moraine make approach to the south faces of the Colque Cruz rather long-winded. Jatunhuma II would be best approached via the Campa Col a few kilometers to the northeast of Ausangate. Our problem was lack of time and reasonable weather in the latter stages of our expedition when we were acclimatized.

Simon Cooke, United Kingdom