The Sierra Nevada (/siˌɛrə nɪˈvædə, -ˈvɑːd-/ see-ERR-ə nih-VA(H)D-ə)[6][a] is a mountain range in the Western United States, between the Central Valley of California and the Great Basin.

The Sierra Nevada is part of the American Cordillera, an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas.

[3] Notable features include General Sherman, the largest tree in the world by volume; Lake Tahoe, the largest alpine lake in North America; Mount Whitney at 14,505 ft (4,421 m),[1] the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers from one-hundred-million-year-old granite, containing high waterfalls.

The uplift caused a wide range of elevations and climates in the Sierra Nevada, which are reflected by the presence of five life zones (areas with similar plant and animal communities).

[15][16] Ansel Adams, in response to a publication of his photographs under the title Parmelian Prints of the High Sierras, commented, "To add an s is a linguistic, Californian, and mountaineering sin.

It represents where the granitic bedrock of the Sierra Nevada dives below the southern extent of Cenozoic igneous surface rock from the Cascade Range.

[21] It is bounded on the west by California's Central Valley, on the east by the Basin and Range Province, and on the southeast by the Mojave Desert.

The California Geological Survey states that "the northern Sierra boundary is marked where bedrock disappears under the Cenozoic volcanic cover of the Cascade Range.

The southern third of the range is drained by the Kings, Kaweah, Tule, and Kern rivers, which flow into the endorheic basin of Tulare Lake, which rarely overflows into the San Joaquin during wet years.

Although none of the eastern rivers reach the sea, many of the streams from Mono Lake southwards are diverted into the Los Angeles Aqueduct which provides water to Southern California.

Within these national parks, monuments, and forests lie 26 wilderness areas, which together protect 15.4% of the Sierra's 63,118 km2 (24,370 sq mi) from logging and grazing.

[28] These dark-colored hornfels, slates, marbles, and schists are found in the western foothills (notably around Coarsegold, west of the Tehachapi Pass) and east of the Sierra Crest.

[30] In the Triassic and into the Jurassic, an island arc collided with the west coast of North America and raised a chain of volcanoes, in an event called the Nevadan orogeny.

[34] During this period, rivers cut deep canyons into the range, generating topographic relief similar to the modern Sierra Nevada.

This period of incision was halted approximately 30 million years ago by vast outpourings of pyroclastic flows from Nevada which filled the northern Sierran valleys with volcanic deposits.

[35] These pyroclastic flows, which continued for about 10 million years, were followed by andesitic lahars which nearly completely buried the northern Sierran landscape such that only the tallest peaks emerged above a volcanic plain.

The combination of river and glacier erosion exposed the uppermost portions of the plutons emplaced millions of years before, leaving only a remnant of metamorphic rock on top of some Sierra peaks.

This is a horizontal rotation of the atmosphere just east of the crest of the Sierra, set in motion as an effect of strong westerly winds.

Hypotheses that the crashes are related in some way to the United States Air Force's Area 51, or to the activities of extra-terrestrial aliens, have no evidence to support them.

The rain shadow of the Sierra causes the eastern slope to be warmer and drier: each life zone is higher in the east.

[33] A list of biotic zones, and corresponding elevations, is presented below: Archaeological excavations placed Martis people of Paleo-Indians in northcentral Sierra Nevada during the period of 3,000 BCE to 500 CE.

[56] The first Americans to visit the mountains were amongst a group led by fur trapper Jedediah Smith, crossing north of the Yosemite area in May 1827, at Ebbetts Pass.

It is estimated that by the mid-1880s, 11 million troy ounces (340 metric tons) of gold (worth approximately US$16 billion in 2020 prices) had been recovered by "hydraulicking".

[67] A consequence of these extraction methods was that large amounts of gravel, silt, heavy metals, and other pollutants were washed into streams and rivers.

[66]: 32–36  As of 1999[update], many areas still bear the scars of hydraulic mining, since the resulting exposed earth and downstream gravel deposits do not support plant life.

[63]: 25  The huge numbers of newcomers brought by the Gold Rush drove Native Americans out of their traditional hunting, fishing and food-gathering areas.

Men of the survey, including William H. Brewer, Charles F. Hoffmann and Clarence King, explored the backcountry of what would become Yosemite National Park in 1863.

[76]: 142–144  These companies had the financial resources to transport timber from remote locations and build sawmills near the tracks of the Southern Pacific railroad which connected the San Joaquin Valley to the rest of the state in the 1870s.

In addition, technological advancements, such as the shay locomotive and the v-shaped log flume, made it easier to transport lumber across mountainous terrain.

In the 1920s, automobile clubs and nearby towns started to lobby for trans-Sierra highways over Piute Pass[82] (which would have closed the gap in SR 168) and other locations.