Cordillera de Potosí. This range, nine miles east of historic Potosí, has some 50 rock peaks between 4800 meters and the highest, 5056-meter (16,590-foot) Cururana. With no glaciers, it is seldom visited by climbers. It receives heavy snow between December and March, but the summer, June to August, is usually dry, though cold and windy. I had visited the range in 1985 (AAJ, 1986, page 196) and returned in April 1993, to traverse from south to north and to climb. From Potosí I rode to the Andacaba mine, which gave access to the southern end of the range. On April 28, from a 4420-meter camp in the Muyucocha valley, I ascended easy P 4940 (16,208 feet), which I named “Cerro de la Mina,“ a first ascent. From it, I traversed south to Hembra de Andacaba (4980 meters, 16,339 feet), which had been climbed several times before. I then traversed the southern part of the range from south to north, crossing the Casiri gap and the Jacha Molino Pampa hills. From Lake Sipuruni, I climbed P 5000 (16,404 feet), north of Jatún Condoriri. The same day, May 3, I traversed north to ascend P 4966 (16,294 feet), which I called “Sipuruni.” Both summits showed traces of a previous visit. Finally, I reached the Jatún Casa Pass. From it, on May 5 I climbed Quellu Orco (4960 meters, 16,273 feet), a first ascent. On my second campaign, I entered the drought-stricken Ildefonso valley and crossed the Quespi Llacta Pass at its head. From camp in the Quespi Llacta valley, on May 12 I climbed the steep pyramid of P 4940 (16,208 feet), called Maucatambo on the old maps. The rock was excellent. To my surprise, I found on the top an Indian altar: two candles, a small bag of coca leaves and two bottles of liquor. This was no doubt an offering to Pachamama, the goddess Earth, to have the havoc of the drought stopped. Two days later, I found a similar altar on top of Jucuni (4920 meters, 16,142 feet). Bad weather forced me to return to Potosí. All names are being submitted to the Institute Geográfico Militar de Bolivia.