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The Sierra Nevada is a mountain range that is mostly in eastern California. The range is also known as The Sierra or The Sierras. 
GeographyThe Sierra Nevada stretches 400 miles (650 km), from Fredonyer Pass in the north to Tehachapi Pass in the south. It is bounded on the west by California's Central Valley, and on the east by the Great Basin. In west-east cross section, the Sierra is shaped like a non-equilateral triangle: the altitude gradually increases as you travel east, until you reach the crest, whereupon the altitude rapidly decreases. Thus, the crest runs principally along the eastern edge of the Sierra Nevada range. Rivers flowing west from the Sierra crest eventually drain into the Pacific Ocean, while rivers draining east flow into the Great Basin and do not reach any ocean. However, water from several streams and the Owens River is redirected to the city of Los Angeles (see Los Angeles Aqueduct). Thus, some east-flowing river water does make it to the Pacific Ocean. There are several notable geographical features in the Sierra Nevada:
The height of the mountains in the Sierra Nevada gradually increases from north to south. Thus, the crest near Lake Tahoe is roughly 9000 ft (2,700 m) high, the crest near Yosemite National Park is roughly 13000 ft (4,000 m) high, and the entire range attains its peak at Mount Whitney. South of Mount Whitney, the range quickly diminishes in elevation. Geology See Geology of the Yosemite area for a detailed article about the geology of the central Sierra Nevada. The geological history of the Sierra Nevada begins in the Jurassic Era, approximately 150 million years ago. At that time, an island arc collided with the West coast of North America and raised a set of mountains, in an event called the Nevadan orogeny. This event produced metamorphic rock. At roughly the same time, a subduction zone started to form at the edge of the continent. This means that an oceanic plate started to dive beneath the North American plate. Magma from the melting oceanic plate rose and created plutons of solid granite, deep below the surface. These plutons formed at various times, from 115 million to 87 million years ago. By 65 million years ago, the proto-Sierra Nevada was worn down to a range of rolling low mountains, a few thousand feet high. About 25 million years ago, the Sierra Nevada started to rise and tilt to the west. Rivers started cutting deep canyons on both sides of the range. The Earth's climate cooled, and ice ages started about 2.5 million years ago. Glaciers carved out characteristic U-shaped canyons throughout the Sierra. The combination of river and glacier erosion exposed the granitic plutons previously buried, leaving only a remnant of metamorphic rock on top of some Sierra peaks. Uplift of the Sierra Nevada continues today, especially along its eastern side. This uplift causes large earthquakes, such as the Lone Pine earthquake of 1872. BiologyMain article: Biology of the Sierra Nevada Allan Schoenherr divides the Sierra Nevada into a number of biotic zones:
HistoryHistory of ExplorationThe earliest identified inhabitants of the Sierra Nevada were the Paiute tribe on the east side and the Miwok tribe on the west. These tribes traded goods by meeting at and traveling over mountain passes. Even today, passes such as Duck Pass are littered with discarded obsidian arrowheads, which are remnants of the trading. In the winter of 1844, Lieutenant John C. Frémont, accompanied by Kit Carson, was the first white man to see Lake Tahoe.  By 1860, even though the California gold rush populated the flanks of the Sierra Nevada, most of the Sierra remained unexplored. Therefore, the state legislature authorized the California Geological Survey to officially explore the Sierra (and survey the rest of the state). Josiah Whitney was appointed to head the survey. Men of the survey, including William Brewer, Charles Hoffmann, and Clarence King, explored the backcountry of what would become Yosemite National Park in 1863. In 1864, they explored the area around Kings Canyon. King later recounted his adventures over the Kings-Kern divide in his book Mountaineering in the Sierra Nevada. In 1871, King mistakenly thought that Mount Langley was the highest peak in the Sierra and climbed it. However, before he could climb the true highest peak (Mount Whitney), fishermen from Lone Pine, California climbed it and left a note. Between 1892 and 1897, Theodore Solomons was the first explorer to attempt to map a route along the crest of the Sierra (what would eventually become the John Muir Trail, along a different route). On his 1894 expedition, he took along Leigh Bierce, son of writer Ambrose Bierce.  Other noted early mountaineers included: Features in the Sierra are named after these men. History of the NameSierra Nevada means "snowy range" in Spanish. In April of 1776, Padre Pedro Font on the second de Anza expedition gave that name to the mountains that could be seen in the distance to the east. Its most common nickname is the Range of Light. This nickname comes from John Muir, who in 1894 wrote in The Mountains of California:
This description is due to the unusually light colored granite exposed by glacial action. Interesting factsA unique peculiarity of the Sierra Nevada is that, under certain wind conditions, a large circular tube of air begins to roll on the southeast side. This "rotor" is so perfectly symmetrical that it drives a series of higher counter-rotating rotors. This effect proceeds higher than most aircraft are able to reach. All recent world altitude records set in unpowered aircraft were set in the Sierra Nevada Rotor, most flown from Mojave Airport. The Sierra Nevada casts the valleys east of the Sierra in a rain shadow, which makes Death Valley and Owens Valley "the land of little rain". ListsPrincipal MountainsList of mountains over 14,000 ft (4250 m) with 300 ft (90 m) of prominence [1] (http://www.peakbagger.com/list.aspx?lid=21320):
Other notable peaks:
Counties in the Sierra
The Carson Range (often considered part of the Sierra) extends into Nevada: Principal rivers and lakes
Other natural features
National parks and monumentsNorth to south:
Eastern side of the Sierra: National forests
Wilderness areasA total of approximately 5300 square miles (13,700 km²):
Trails and routesExternal links
References
See also: List of guidebooks about the Sierra Nevada
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