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
Gilgit-Baltistan to the north, and the Hindu Kush lies to the west. Amongst the highest mountains are K2 (Mount Godwin-Austen) and Nanga Parbat, the latter being one of the most feared mountains in the world. Three of the world's longest glaciers outside the polar regions are found in Gilgit-Baltistan: the Biafo Glacier, the Baltoro Glacier, and the Batura Glacier. There are, in addition, several high-altitude lakes in Gilgit-Baltistan: The Deosai Plains, are located above the tree line and constitute the second-highest plateau in the world at 4,115 metres (14,500 feet) after Tibet. The plateau lies east of Astore, south of Skardu