Rí o Blanco Group. In January 1955 Jorge and Sergio Domicelj, Juan Guthmann, Fredy Klayman, and Carlos Stegmann of the Centro Andino, Buenos Aires, climbed in the Río Blanco Group, which lies just to the south of Aconcagua. From a base camp at 10,300 feet in the Quebrada de Vargas they established a Camp 1 at 14,000 feet and Camp 2 on the Upper Rio Plomo Glacier at 16,000 feet. The Domicelj brothers and Klayman made the third ascent of 17,036-foot Cerro León Blanco, while Guthmann and Stegmann attempted 17,373-foot Cerro Río Blanco, where they failed be­ cause of bad weather. Storms drove them back to their base, from which some four days later the first three made the first ascent of a 15,708-foot peak on the Chilean-Argentine frontier about two miles north of Cerro Leon Blanco. This they called Cerro Gustavo. The other two meanwhile made the second ascent of the Cerro Central (17,205 feet) from Camp 1.