HuaynaPotosí, West Rib, Cordillera Real. In July of 1989, my wife Julie and I repeated the Lyon route on the massive west face of Huayna Potosí. Our attention was held by the 3000 feet of 50° to 65° ice, but we couldn’t help noticing the distinct rock-and-ice arête that bounded the northern side of the west face. In August of 1990, we returned and did what we believe is the first complete ascent of the entire west rib. Our climb began with 55° ice, rock and mixed climbing at about 16,400 feet. After three hours on the rib, we chopped a ledge out of the ice and snow at 18,000 feet at the last major snow rib on the route for a bivouac. The next day, August 25, we encountered progressively more difficult mixed terrain with rock moves up to 5.8. Continuous snowfall made the climbing more tedious. Julie led a thin ice-veneer pitch that involved down- climbing 75° water ice with only a tied-off Lost Arrow for protection. Several more pitches of 60° to 65° water ice led us to the final major rock buttress at 19,400 feet. Rock climbing (5.8) on rotten blocks was protected by a single tied-off screw. Spectacular, steep ridge-and-comice climbing with rapidly fading light found us simul-climbing the final 70° ice arête in the dark. We descended to 19,500 feet on the normal route to spend a stormy night.
Matt Culberson, American Alpine Institute