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
Region of the 10 Thousanders Region of the 10 Thousanders The Region of the 10 Thousanders () is a region in the Swabian Jura in the German state of Baden-Württemberg, the name of which alludes to the high mountain peaks in the area. Almost all the highest mountains of the Swabian Jura (each over ), including their highest summit (), are located in this relatively small region which only covers 20 km² around Deilingen, Wehingen and Gosheim in the southwestern Jura. The name "Region of the 10 Thousanders" goes back to an action group that was initiated by various restaurants and municipalities of the Heuberg