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5/17/11 – American guide Michael Horst has climbed Mt. Everest and Lhotse, the highest and fourth-highest mountains in the world, with less than 21 hours between the two summits. Horst summited Everest at 9:30 a.m. on May 14 from the South Col, with Alpine Ascents client Rob Hart. After returning to Camp IV in the South Col, Horst rested and then set out at midnight for Lhotse, on the other side of the pass. He topped out at 5:50 a.m. on May 15.
Horst benefitted from the use of supplementary oxygen during the climbs and while resting at the South Col, and he was aided by a pair of Sherpa climbers employed by Alpine Ascents, who fixed 1,800 feet of rope on Lhotse while Horst and Hart were climbing Everest. Nonetheless, it was a remarkable achievement—possibly the first time these two peaks have been climbed without a return to base camp.
Dates of ascents: May 13-15, 2011