John Muir (April 21, 1838 - December 24, 1914) also known as John of the Mountains and Father of the National Parks , was an influential Scottish-American naturalist, author, environmental philosopher, glaciologist and early advocate for the preservation of wilderness in the United States. His letters, essays, and books describing his adventures in nature, especially in the ... Read moreSierra Nevada, have been read by millions. His activism has helped to preserve the Yosemite Valley, Sequoia National Park and many other wilderness areas. The Sierra Club, which he co-founded, is a prominent American conservation organization. Show Less