Ellis made two attempts to climb Mount Everest, the world's highest mountain. In 1988, he was part of the expedition that was successful in putting the first two American women on the summit. Ellis, who also had been a long-distance runner who had previously qualified as an Olympic distance runner before he became a climber, was drawn to climbing in 1981 after seeing Mount Everest while at a seminar on Third World medicine in Nepal. Dr. Ellis qualified for the U.S. Olympic Trials as a marathon runner in 1980, the year the United States boycotted the Summer Games in Moscow. In 1996 Dr. Ellis became the first African-American to summit an 8,000 meter peak, this being a benchmark for climbers. The peak, Cho Oyu, in Tibet, is the sixth highest mountain in the world and one of only 14 peaks higher than 8,000 meters.