Mountain Madness interests. While leading Mountain Madness, Fischer became renowned for his ascents of the world's highest mountains made without the use of supplemental oxygen. Fischer and Wally Berg were the first Americans to summit Lhotse, the world's fourth highest mountain (27,940 feet / 8516 m), located next to Mount Everest. He and Ed Viesturs were the first Americans to summit K2, (28,251 feet / 8611m) in the Karakoram of Pakistan without supplemental oxygen. During his stewardship of Mountain Madness, Fischer led social and environmental initiatives to help people in the countries in which Mountain Madness traveled. As the leaders of the
K2 around 300 successful summits and 77 fatalities; about one person dies on the mountain for every four who reach the summit. It is more difficult and hazardous to reach the peak of K2 from the Chinese side, so it is usually climbed from the Pakistani side. K2 has never been climbed during winter, unlike Annapurna, the mountain with the highest fatality-to-summit rate (191 summits and 61 fatalities), or the other eight-thousanders. Ascents have almost always been made in July and August, the warmest times of year; K2's more northern location makes it more susceptible to inclement and colder weather. The