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
Karakoram and Pamir mountains have been nominated for inclusion in UNESCO in 2010 by the National Commission of the People's Republic of China for UNESCO and has tentatively been added to the list. Karakoram is a Turkic term meaning "black gravel". The Central Asian traders originally applied the name to the Karakoram Pass. Early European travellers, including William Moorcroft and George Hayward, started using the term for the range of mountains west of the pass, although they also used the term Muztagh (meaning, "Ice Mountain") for the range now known as Karakoram. Later terminology was influenced by the Survey of India,