New Zealand Expedition to Pumasillo Group, Cordillera Vilcabamba. English and Swiss expeditions to the Cordillera Vilcabamba sent us tempting reports of two worthy unclimbed ice peaks, Mitre (19,000 feet) and Sacsarayoc (20,000 feet) and as added inducement there were the regions northeast of Pumasillo and those south to the Yanama Range that required exploration and mapping. By June 7 our seven-man party, comprising Brian Hearfield, leader; Victor Walsh, deputy leader; Lyn Crawford, Peter Farrell, Hans Furndorfler, Bruce Naylor and Donald Mackay, had established Base Camp at 14,500 feet in the Pumasillo basin, our route having followed that chosen by the British party, i.e. Vilcabamba River, Choquetacarpo Pass, Pumasillo. The next day we started to reconnoitre a tortuous route through the icefall on Mitre to the only campsite available at 17,500 feet, above which the route soared swiftly to the almost vertical summit face. From this high camp Crawford, Farrell, Furndorfler and Walsh on June 11 climbed the mountain, partly via its north face, then through a short ice tunnel to its south face; the final section consisted of south-facing snow overlying ice on a slope of 85°. Before attempting Sacsarayoc, which lies four miles south along the mountain chain from Mitre, we decided to climb the other peaks at the head of the Pumasillo basin, Choquetacarpo, Kaiko and Redondo, all ascended by the Swiss in 1959. The former was the most interesting of these three and was climbed by Farrell and Crawford on the north face and by Furndorfler and me on the east ridge.

Sacsarayoc was next on the agenda, but after closely inspecting the southern and western faces, we favoured a traverse of the main range over Cabeza Blanca, little knowing what we were in for. Establishment of a high camp at 18,000 feet on Pumasillo’s west ridge above steep flutings proved an exhausting task, as it was necessary to relay and rope the 400 lbs. of gear up a considerable height on the mountain. And the traverse to Sacsarayoc was not successful in spite of repeated attempts; the snow ridge beyond Cabeza Blanca dropped off in a series of vertical drops, all fearfully overhanging and very unstable. On the third attempt a point was reached halfway along the ridge to Sacsarayoc before safety considerations compelled an abandonment, and so we consoled ourselves with the third ascent of Pumasillo (Farrell and I) and the second of Cabeza Blanca before packing up and returning to Base. Meanwhile the other three members had been successfully climbing and mapping in the two regions that were virtually unexplored. They had covered a lot of territory, involving heavy pack-swagging over long distances and across high passes. We were determined to make an all-out final attempt on Sacsarayoc. With the southern approach hopeless in waist-deep snow and the western face exposed and menaced by overhanging ice blocks, there remained but one final route, the east ridge that ran from the summit along to an unnamed and unclimbed 19,000-foot peak before ending in the fine 20,000-foot ice peak, Lasontay (also called Lasonayoc ; first ascent by Arnis, Ayres, Matthew, Michael, 1956. AAJ 1957, 10:2, pp. 64-8.—Editor.) But how could we cross into the huge eastern basin formed by this great ring of peaks? Fortunately the survey party when climbing on the Yanama Range had noticed and explored an accessible glacier draining Lasontay which joined the Yanama River near its head. Mules were engaged for the two-day march to our new Base Camp, which was finally situated at about 15,000 feet in a narrow, grass-covered ablation valley only three hours below a low snow col between Lasontay and its eastern outlier. In deteriorating weather, we moved straight in with loads to try to reach a high camp without reconnaissance, but this proved most unwise. We soon found, on reaching the big northeast ridge of Lasontay, that the slopes into the main basin dropped away almost vertically, and we were forced to carry the loads higher and higher up the mountain before finally roping them down into the easier slopes of the upper basin. After two very tiring days we had our camp pitched between Lasontay and its western virgin neighbor, from where we eagerly scanned the big, difficult ice step on Sacsarayoc’s east ridge. This later proved to be problem enough! After a night out just a few hundred feet from the summit, with one man above the ice step and three men below it, Farrell alone moved on to the now easier summit slopes to put a finish to the long battle for Sacsarayoc. After a day’s rest, Walsh and Naylor climbed the virgin 19,000-foot peak east of Sacsarayoc by its north face and Farrel and I, Lasontay via its steep north-west face. On July 23 we were back in Base to find that our companions had been active again on the Yanama Range and particularly on Quishua, but a driving snowstorm foiled their success on this fine mountain. After crossing the Yanama Pass and descending the lovely Santa Teresa valley, we reached the railhead at Huadquiña on July 28. Peaks climbed with approximate heights and routes follow. First ascents: Mitre, 19,000 feet, north and south faces, June 11; Rock Top, 17,000 feet, south ridge, June 23; Nevada Blanca, 18,000 feet, south ridge, June 25; unnamed south of Pucapuca, 17,500 feet, northeast face, June 30; Puerta de Yanama, 18,0 feet, northwest face, July 5 ; Sacsarayoc, 19,800 feet, east ridge, July 18-9; unnamed peak between Sacsarayoc and Lasontay, 19,000 feet, north face, July 21. Second ascents: Kaiko, 17,250 feet, east ridge, June 15; Redondo, 17,300 feet, west ridge, June 15; Choquetacarpo, 18,000 feet, east ridge and north face, June 16; Pucapuca, 17,900 feet, east face June 18; Cabeza Blanca, 19,500 feet, west ridge, June 27 & 28, July 5; unnamed peak east of Lasontay, 17,500 feet, west ridge, July 6; Lasontay, 20 000 feet, northwest face, July 21. Third ascent: Pumasillo, 20,000 feet, west ridge, June 28.

Brian Hearfield, New Zealand Alpine Club