The Site preserves the 14 room mansion where the naturalist John Muir lived from 1890 to his death in 1914. While living in Martinez, Muir accomplished many things: he battled to prevent Yosemite National Park's Hetch Hetchy Valley from being dammed, served as the first president and one of the founders of the Sierra Club, played a prominent role in the creation of several national parks, and hundreds of newspaper and magazine articles and several books expounding on the virtues of conservation and the natural world. Muir's work laid the foundations for the creation of the National Park Service in 1916. The Muir house and historic Martinez adobe became part of the National Park Service in 1964. In 1992, Mt. Wanda was added to the Site. The 325 acre tract of oak woodland and grassland was historically owned by the Muir family.