When he came to California and finally settled in San Francisco, John Muir immediately left for a visit to Yosemite, a place he had only read about. Seeing it for the first time, Muir noted that "He was overwhelmed by the landscape, scrambling down steep cliff faces to get a closer look at the waterfalls, whooping and howling at the vistas, jumping tirelessly from flower to flower." He climbed a number of mountains, including Cathedral Peak and Mount Dana, and hiked the old Indian trail down Bloody Canyon to Mono Lake. He lived in the cabin for two years, and wrote about this period in this book My First Summer in the Sierra. John Muir was a Scottish-American naturalist, author, environmental philosopher and early advocate of preservation of wilderness in the United States. His letters, essays, and books telling of his adventures in nature, especially in the Sierra Nevada mountains of California, have been read by millions. His activism helped to preserve the Yosemite Valley, Sequoia National Park and other wilderness areas. The Sierra Club, which he founded, is a prominent American conservation organization.