The Coast Ranges of
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
span from
Del Norte or
Humboldt County, California
Humboldt County () is a county (United States), county located in the U.S. state of California. As of the 2020 United States census, 2020 census, the population was 136,463. The county seat is Eureka, California, Eureka.
Humboldt County compri ...
, south to
Santa Barbara County
Santa Barbara County, officially the County of Santa Barbara (), is a county located in Southern California. As of the 2020 United States census, the population was 448,229. The county seat is Santa Barbara, and the largest city is Santa M ...
.
The other three coastal California mountain ranges are the
Transverse Ranges,
Peninsular Ranges and the
Klamath Mountains
The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast R ...
.
Physiographically, they are a section of the larger
Pacific Border province
The Pacific Border province is a physiographic province of the Physiographic regions of the world physical geography system.
Description
The Pacific Border province encompasses most of the North American West Coast of the United States, Pacifi ...
, which in turn is part of the larger
Pacific Mountain System physiographic division.
UNESCO
The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...
has included the "
California Coast Ranges Biosphere Reserve" in its
Man and the Biosphere Programme
Man and the Biosphere Programme (MAB) is an intergovernmental scientific program, launched in 1971 by UNESCO, that aims to establish a scientific basis for the 'improvement of relationships' between people and their environments.
MAB engages w ...
of
World Network of Biosphere Reserves since 1983.
[
*]
Physiography

The northern end of the California Coast Ranges overlap the southern end of the
Klamath Mountains
The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast R ...
for approximately on the west. They extend southward for more than to where the coastline turns eastward along the
Santa Barbara Channel, around the area of
Point Conception. Here the southern end meets the Los Angeles
Transverse Ranges, or ''Sierras de los Angeles''.
The rocks themselves that comprise the mountains are of a great variety and widely varying geologic ages. Most of the rocks were formed during the
Tertiary,
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...
and
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...
periods. Most were deposited on the sea bottom as sediments, but in many places also had cracks, crevices and other gaps infused with molten lava or other masses of
igneous rock
Igneous rock ( ), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava.
The magma can be derived from partial ...
, which were forced in molten condition into the sedimentary rocks. All of the range has been
folded and
faulted during several periods, with erosion of the softer rock giving much of the current appearance.
Mineralogy
The California Ranges had a high production of
mercury following the discovery of gold in the
Sierra Nevada
The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...
. In the
Cache Creek Basin,
Cenozoic
The Cenozoic Era ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterized by the dominance of mammals, insects, birds and angiosperms (flowering plants). It is the latest of three g ...
cinnabar
Cinnabar (; ), or cinnabarite (), also known as ''mercurblende'' is the bright scarlet to brick-red form of Mercury sulfide, mercury(II) sulfide (HgS). It is the most common source ore for refining mercury (element), elemental mercury and is t ...
deposits near
Clear Lake are the northernmost of a group of similar deposits associated with volcanism and migration of a transform fault system. During 1877, these deposits hit their peak production of mercury, producing approximately . These abandoned mines are still a source of mine waste runoff in Cache Creek and other downstream bodies of water.
Northern Coast Ranges
The Northern Coast Ranges are a section of the California Coast Ranges. They run parallel to the
Pacific Coast from the
North San Francisco Bay Area to coastal
Del Norte County. The
Klamath Mountains
The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast R ...
, including the
Siskiyou Mountains
The Siskiyou Mountains are a Coast Ranges, coastal subrange of the Klamath Mountains, and located in northwestern California and southwestern Oregon in the United States. They extend in an arc for approximately from east of Crescent City, Calif ...
sub-range, lie to the north and northeast. The Southern Coast Ranges lie to the south.
Geography
The Northern Coast Ranges run north–south parallel to the coast. Component ranges within the Northern Coast Ranges include the
Mendocino Range of western
Mendocino County and the
Mayacamas,
Sonoma, and
Vaca Mountains and the
Marin Hills of the
North Bay.
They also include the
King Range, which meet the sea in the "
Lost Coast" region. The southernmost peak of the Northern Coast Ranges is
Mount Tamalpais
Mount Tamalpais (; ; Miwok languages, Miwok: ''Támal Pájiṣ''), known locally as Mount Tam, is a mountain, peak in Marin County, California, Marin County, California, United States, often considered symbolic of Marin County. Much of Mount Tama ...
.
The highest point in the Northern Coast Ranges is
Mount Linn, at 8,098 ft. (2,468 m).
Outer and Inner ranges
The Northern Coast Ranges consist of two main parallel belts of mountains, the Outer Northern Coast Ranges lying along the coast, and the Inner Northern Coast Ranges running inland to the east. They are separated by a long system of valleys. The northern valley portion is drained by the
Eel River and its tributaries, and the southern by the
Russian River. A series of short rivers, including the
Mattole,
Gualala, and
Navarro rivers, drain the western slopes of the ranges. The eastern slopes of the ranges drain into the
Sacramento Valley.
Clear Lake lies in the southeast portion of the range, and drains eastward via
Cache Creek.
U.S. Route 101 runs generally north–south in the valleys between the Outer and Inner Northern Coast Ranges.
Natural history

The seaward face of the coastal Outer Northern Coast Ranges is part of the
Northern California coastal forests
Northern may refer to the following:
Geography
* North, a point in direction
* Northern Europe, the northern part or region of Europe
* Northern Highland, a region of Wisconsin, United States
* Northern Province, Sri Lanka
* Northern Range, a ...
ecoregion, home to lush forests of
Coast Redwood and
Coast Douglas-fir
''Pseudotsuga menziesii'' var. ''menziesii'', commonly known as Coast Douglas-fir, Pacific Douglas-fir, Oregon pine, or Douglas spruce, is an evergreen conifer native to western North America from west-central British Columbia, Canada southward t ...
.
The inland and dryer Inner Northern Coast Ranges are part of the
California chaparral and woodlands ecoregion, home to a number of plant communities including:
mixed evergreen forest;
oak woodland; and
Interior chaparral and woodland. A major specific plant community of the inner ranges is
Mediterranean California Lower Montane Black Oak-Conifer Forest, which supports particularly high
biodiversity
Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distribut ...
within the California Coast Ranges, including the nominate
California Black Oak.
Columbian
Black-tailed Deer are the most widespread large mammal, after humans, of the Northern Coast Ranges. The rivers in the ranges are home to several species of
salmon
Salmon (; : salmon) are any of several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the genera ''Salmo'' and ''Oncorhynchus'' of the family (biology), family Salmonidae, native ...
.
Southern Coast Ranges
Geography
The Southern Coast Ranges, of the California Coast Ranges in the Pacific Coast Ranges System, run north and south, parallel to the Pacific Coast in north-central through north-southern California. The Southern Coast Ranges begin on the
San Francisco Peninsula and in the
East San Francisco Bay Area, and run south into
Santa Barbara County
Santa Barbara County, officially the County of Santa Barbara (), is a county located in Southern California. As of the 2020 United States census, the population was 448,229. The county seat is Santa Barbara, and the largest city is Santa M ...
. The
Transverse Ranges lie to the south. The
San Joaquin Valley
The San Joaquin Valley ( ; Spanish language in California, Spanish: ''Valle de San Joaquín'') is the southern half of California's Central Valley (California), Central Valley. Famed as a major breadbasket, the San Joaquin Valley is an importa ...
is on the east, and Pacific Ocean on the west.
The Southern Coast Ranges include the
Berkeley Hills, the
Diablo Range, the
Santa Cruz Mountains, the
Gabilan Range, the
Santa Lucia Range and
Sierra de Salinas, the
Temblor Range, and the
Sierra Madre.
There are Outer Southern Coast Ranges along the Pacific Ocean on the west, and Inner Southern Coast Ranges to the east, inland to the
San Joaquin Valley
The San Joaquin Valley ( ; Spanish language in California, Spanish: ''Valle de San Joaquín'') is the southern half of California's Central Valley (California), Central Valley. Famed as a major breadbasket, the San Joaquin Valley is an importa ...
. The central and southern
San Francisco Bay
San Francisco Bay (Chochenyo language, Chochenyo: 'ommu) is a large tidal estuary in the United States, U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the cities of San Francisco, California, San ...
and the
Salinas Valley lie between them.
The highest point of the Southern Coast Ranges is
Junipero Serra Peak in the Santa Lucia Range, at .
Other peaks include
Mount Diablo
Mount Diablo is a mountain of the Diablo Range, in Contra Costa County, California, Contra Costa County of the eastern San Francisco Bay Area in Northern California. It is south of Clayton, California, Clayton and northeast of Danville, Califo ...
at , and
Mount Hamilton at .
Natural history
The Southern Coast Ranges have a predominantly
Mediterranean climate
A Mediterranean climate ( ), also called a dry summer climate, described by Köppen and Trewartha as ''Cs'', is a temperate climate type that occurs in the lower mid-latitudes (normally 30 to 44 north and south latitude). Such climates typic ...
, and are primarily within the
California chaparral and woodlands ecoregion
An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...
. However, the moister areas of the
Santa Cruz Mountains lie within the
Northern California coastal forests
Northern may refer to the following:
Geography
* North, a point in direction
* Northern Europe, the northern part or region of Europe
* Northern Highland, a region of Wisconsin, United States
* Northern Province, Sri Lanka
* Northern Range, a ...
ecoregion, characterized by forests of
Coast redwood. Isolated groves of Coast redwoods are also found in the
Big Sur region of the Santa Lucia Range, making them the southernmost natural occurrences of the species.
Some of the rarest forest
habitat
In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...
that occurs in the California Coast Ranges are the
Maritime Coast Range Ponderosa Pine forests of the western Santa Cruz Mountains.
[Earth Metrics Inc. (1990) ''Environmental Impact Report for the Scotts Valley Redevelopment Area'', State of California Clearinghouse Report 7888, Sacramento, California] These isolated groves may include
Ponderosa pine,
Douglas fir, and
knobcone pine.
Notably, the highest slopes of the Santa Lucias contain small patches of Sierran Conifer forest, including
incense cedar, and ponderosa, Jeffrey, and
sugar pines. Steep rocky slopes harbor the endemic
Santa Lucia Fir, the rarest species of fir on earth.
The California chaparral and woodlands ecoregion has a great range of plant communities in the Southern Coast Ranges, including
mixed evergreen forests,
oak woodland and
savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...
s,
grassland
A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...
s,
northern coastal scrub
Northern coastal scrub is a diverse scrubland plant community found along the Pacific Coast from Northern California to Southern Oregon, as well as some offshore islands. It frequently forms a landscape mosaic with California coastal prairie, coast ...
, and the
Monterey Pine
''Pinus radiata'' (synonym (taxonomy), syn. ''Pinus insignis''), the Monterey pine, insignis pine or radiata pine, is a species of pine native to the Central Coast (California), Central Coast of California and Mexico (on Guadalupe Island and Ced ...
woodlands of the
Monterey Peninsula and two other coastal enclaves of the Santa Lucia Range. The name "
chaparral
Chaparral ( ) is a shrubland plant plant community, community found primarily in California, southern Oregon, and northern Baja California. It is shaped by a Mediterranean climate (mild wet winters and hot dry summers) and infrequent, high-intens ...
" comes from the
Spanish word
chaparro, applied to
California scrub oaks and
Coastal scrub oaks.
Common tree species of oak woodlands include oaks,
California bay, and
buckeye.
Riparian species of the coast ranges include
sycamore,
white alder,
willows, and
bigleaf maple.
Columbian
Black-tailed deer occupy the northern and more coastal portions of the Southern Coast Ranges, and
California mule deer occupy inland and southernmost portions of the Southern Coast Ranges.
Ranges
*
Bald Hills
*
Berkeley Hills
*
Caliente Range
*
Chalk Mountains
*
Diablo Range
*
Gabilan Range
*
King Range
*
La Panza Range
*
Marin Hills
*
Mayacamas Mountains
*
Mendocino Range
*
Santa Cruz Mountains
*
Santa Lucia Range
*
Shelton Buttes Geography
Hydrology
Landscape
Climate
The Shelton Buttes are a mountain group of Buttes in Humboldt County, California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the ...
*
Sonoma Mountains
*
Temblor Range
*
Vaca Mountains
*
Klamath Mountains
The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast R ...
*
Northern Coast Ranges
*
Southern Coast Ranges
*
Transverse Ranges
*
Peninsular Ranges
See also
*
*
Coast Range Geomorphic Province
*
Inner Coast Ranges
*
*
*
North American Cordillera
References
External links
Early History of the California Coast, a National Park Service ''Discover Our Shared Heritage'' Travel Itinerary*Map:
*
{{California
Pacific Coast Ranges
Lists of mountain ranges of the United States
Mountain ranges of California
Mountain ranges of Northern California
Mountain ranges of Southern California
Geologic provinces of California
Physiographic sections
Mountain ranges of the Western United States
Biosphere reserves of the United States
West Coast of the United States