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
Baltistan of mountains in the world and the biggest glaciers outside the polar regions. The Himalayas advance into this region from India, Tibet and Nepal, and north of them are the Karakoram range. Both ranges run northwest, separated by the Indus River. Along the Indus and its tributaries are many valleys. Glaciers include Baltoro Glacier, Biafo Glacier, Siachen Glacier, Trango Glacier and Godwin-Austen Glacier. Baltistan is home to more than 20 peaks of over , including K2 (the second-highest mountain on earth. Other well-known peaks include Masherbrum (also known as K1), Broad Peak, Hidden Peak, Gasherbrum II, Gasherbrum IV and Chogolisa