Cordillera Huanzo. We spent some ten days crossing the high, arid, desolate, volcanic plateaus which separate the departments of Cuzco, Arequipa and Apurímac. We went from Santo Tomás to Antabamba. Getting to Santo Tomás with its irregular traffic was difficult. After an approach from there of three days, Sue Tatum and I climbed Huaychahui (5452 meters or 17,887 feet) on June 1 by its northeast ridge. On the summit we found a small cairn and a broken bottle, probably left by map surveyors long ago. Though this is the most spectacular summit of the range with its ship’s-prow shape, the climb was straightforward, mostly on snow. Staying on the eastern side of the divide, we reached the top of the pass between Chancoaña and Huayunca at 17,150 feet. The southern cirques of Huayunca contain extensive glaciers and snowfields. I climbed Chancoaña (5494 meters or 18,025 feet) solo on June 4 via its northern snow slopes and a last loose volcanic rock pitch, which I think would have been too much for a survey party. There were no traces of previous climbers. It took another three days to reach Antabamba.