On June 26, from a high camp at 5,100m, my wife, Jeanne, and I climbed a possible new variation (grade AD+) to reach the previously climbed east ridge on Chaupi Orco (6,044m). Our route was necessitated by deep, fresh snow that forced us to find a more expedient path to the ridge. Crossing the glacier east of the peak was an arduous affair, with a few kilometers of knee-deep snow covered with a wind-blown crust. Continuing on the circuitous east ridge route, which reaches the crest from the north, was impractical, so we opted for a more direct path.
We ascended a southeast aspect below the ridge, first moving climber’s left below some seracs, then moving back right on a snow ramp squeezed between the seracs and a rock wall. We then climbed directly to the ridge in deep 55° snow. There were moments when the snow was too deep and steep to find purchase and instead left us “swimming.” At these points we were forced to move laterally until enough purchase could be found to continue upward.
Toward the top of the face we moved slightly left and climbed a near vertical section of exposed serac to avoid the “swimming” and so gain the ridge. The snow on the very broad ridge was much more consolidated, and we made better time until a large crevasse was encountered 200m below the summit. We traversed below it to the north, where it terminated on the steep north face. We then climbed a pitch on this face (very good snow and ice) to regain the ridge just before the summit.
On the descent we crossed the crevasse via a snow bridge on the southern flank of the crest. Two double-rope rappels on the southeast face, one from a picket, the other from a V-thread, put us on easier ground that led back to the glacier. Unfortunately, most of our tracks on the glacier had blown over and we were forced to set a new boot-pack back to camp.
A new road completed in the past five years now gives easy access from Pelechuco to this once very remote region of the Apolobamba. We took two days to access the base camp at El Rincon with mules, but it could be reached in one day with a 4x4 vehicle.
Prior to this ascent, we climbed the normal route up the northwest ridge of Acamani (5,450m, AD). This is a fun route in one of the most beautiful regions of all the Andes. We certainly wish to return to the southern Apolobamba for more exploration. [Editor's note: Aaron and Jeanne Zimmerman also made a number of repeat ascents in the Cordillera Real, mostly in the early season (April and May); download the details and photos in this PDF (20mb).]
– Aaron Zimmerman, USA