History of the Yosemite area drainages of two river watersheds. Preservation of watersheds was very important to Muir, who said "you cannot save Yosemite Valley without saving its Sierran fountains." The State of California retained control of Yosemite Valley and the Mariposa Grove of Big Trees. Muir and 181 others founded the Sierra Club in 1892, in part to lobby for the transfer of the valley and the grove into the national park. Like Yellowstone National Park before it, Yosemite National Park was at first administered by various units of the United States Army. Captain Abram Wood led the 4th Cavalry Regiment into the new
Yosemite National Park that moved down the river valleys. Ice thickness in Yosemite Valley may have reached during the early glacial episode. The downslope movement of the ice masses cut and sculpted the U-shaped valley that attracts so many visitors to its scenic vistas today. The name "Yosemite" (meaning "killer" in Miwok) originally referred to the name of a renegade tribe which was driven out of the area (and possibly annihilated) by the Mariposa Battalion. Previously, the area had been called "Ahwahnee" ("big mouth") by indigenous people. Yosemite Valley has been inhabited for nearly 3,000 years, though humans may have first visited the