The Santa Ynez Mountains are a portion of the

Transverse Ranges The Transverse Ranges are a group of mountain ranges of Southern California, in the Pacific Coast Ranges physiographic region in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie within Santa Ba ...

, part of the

Pacific Coast Ranges The Pacific Coast Ranges (officially gazetted as the Pacific Mountain System in the United States; ; ) are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico. Althoug ...

of the west coast of North America. It is the westernmost range in the Transverse Ranges. The range is a large

fault block Fault blocks are very large blocks of rock, sometimes hundreds of kilometres in extent, created by Tectonics, tectonic and localized stresses in Crust (geology), Earth's crust. Large areas of bedrock are broken up into blocks by Fault (geology) ...

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 ...

age created by the movements of the

Santa Ynez Fault Santa Ynez Fault is a left-reverse fault in Santa Barbara County of California. Its length is at least 130 km., running through Santa Ynez and north of nearby Santa Barbara. The Santa Ynez Mountains The Santa Ynez Mountains are a por ...

. A very narrow range, the Santa Ynez Mountains rise quickly on its north side and drops off equally dramatically along the range's south face along the Gaviota Coast. The Santa Ynez Mountains begin as a series of volcanic hills near Point Arguello, and gradually transitions eastward into a single, well-defined ridge extending from Gaviota Peak to Matilija Creek. The range is approximately contiguous with the

Topatopa Mountains The Topatopa Mountains are a mountain range in Ventura County, California, north of Ojai, Santa Paula, and Fillmore. They are part of the Transverse Ranges of Southern California. Etymology A name for the mountains was first inscribed within t ...

beyond to the east, which terminates abruptly at

Sespe Creek Sespe Creek (Chumashan languages, Chumash: S'eqp'e', "Kneecap") is a stream, some long,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed March 16, 2011 in Ventura County, California, Ve ...

. The climate of the range is

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

with most of the precipitation falling between November and March. Most of the range lies in the

California chaparral and woodlands The California chaparral and woodlands is a terrestrial ecoregion of southwestern Oregon, northern, central, and southern California (United States) and northwestern Baja California (Mexico), located on the west coast of North America. It is a ...

ecoregion. At the crest and on the north slope, the rainier regions support extensive oak woodlands, mixed with other broadleafed species such as madrone, sycamore and bay laurel, along with some conifers, primarily Coulter pines.

Geography

The mountains are principally in

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 ...

, with an eastward extension into

Ventura County Ventura County () is a county located in the southern part of the U.S. state of California. As of the 2020 census, the population was 843,843. The largest city is Oxnard, and the county seat is the city of Ventura. Ventura County comprises ...

, and are unusual in being an entirely east–west trending mountain range—one of the few in the United States. This is attributed in part to clockwise rotations of crustal blocks 90° or more since the early

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

or about 17 million years ago. The range is mostly within

Los Padres National Forest Los Padres National Forest is a United States national forest in Southern California, southern and central California. Administered by the United States Forest Service, Los Padres includes most of the mountainous land along the California coast ...

. The southern slopes of the range drop off into a series of alluvial plains which make up the Gaviota Coast along the Santa Barbara Channel. They tend to be made up of unconsolidated riverine deposits overlying shale bedrock. The northern boundary of the range is marked by the Santa Ynez Fault, the massive

thrust fault A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. I ...

that uplifted the mountains since approximately 5 million years ago starting in the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Dibblee Jr, T.W., 1982. Regional geology of the Transverse Ranges Province of southern California. ''Geology and mineral wealth of the California Transverse Ranges'', ''10'', pp.7-26.Minor, S.A., Kellogg, K.S., Stanley, R.G., Gurrola, L.D., Keller, E.A. and Brandt, T.R., 2009. Geologic map of the Santa Barbara coastal plain area, Santa Barbara County, California: US Geological Survey Scientific Investigations Map 3001, scale 1: 25,000, 1 sheet, pamphlet 38 p. Notable features along the fault which mark the boundary of the range include Jalama Creek and the Santa Ynez River to the west and Matilija Creek in the far east. To the north of the range are the San Rafael Mountains. Laterally, the mountains extend from an eastern terminus at the canyon of the Ventura River and Matilija Creek, north of Ojai, west across the Santa Barbara County line, to immediately north of the city of Santa Barbara, and then west, paralleling the coast, to the city of

Lompoc Lompoc ( ; Chumashan ) is a city in Santa Barbara County, California, United States. Located on the Central Coast, its population was 43,834 as of July 2021. Lompoc has been inhabited for thousands of years by the Chumash people, who called t ...

and

Vandenberg Space Force Base Vandenberg Space Force Base , previously Vandenberg Air Force Base, is a United States Space Force Base in Santa Barbara County, California. Established in 1941, Vandenberg Space Force Base is a space launch base, launching spacecraft from the ...

. The Santa Ynez River flows just north of the mountains, paralleling them for most of their length. Before reaching Lompoc the mountain range diverges into two low ridges, separated by Jalama Creek, which then vanish into the Pacific Ocean. The mountains parallel the

Channel Islands The Channel Islands are an archipelago in the English Channel, off the French coast of Normandy. They are divided into two Crown Dependencies: the Jersey, Bailiwick of Jersey, which is the largest of the islands; and the Bailiwick of Guernsey, ...

to the south, another east–west trending range, a geologic extension of the

Santa Monica Mountains The Santa Monica Mountains are a coastal mountain range in Southern California, next to the Pacific Ocean. It is part of the Transverse Ranges. The Santa Monica Mountains National Recreation Area encompasses this mountain range. Because of its p ...

; the two ranges are about thirty miles apart. Principal summits in the Santa Ynez range include Divide Peak, , La Cumbre Peak, (above Santa Barbara), and Santa Ynez Peak, . There are several important passes, including Gaviota Pass in the western portion of the range, through which runs U.S. Highway 101 via the Gaviota Tunnel; and San Marcos Pass near Santa Barbara, through which runs California State Route 154 capped by the magnificent

Cold Spring Canyon Arch Bridge The Cold Spring Canyon Arch Bridge in the Santa Ynez Mountains links Santa Barbara, California with Santa Ynez, California. The bridge is signed as part of California State Route 154, State Route 154. It is currently the highest arch bridge in ...

near the summit. The highest point, an unnamed and unmarked crest colloquially called ''Peak 4864'', is located right above the eastern terminus of the range, near Lake Casitas and Matilija Canyon. Cave in Lizards Mouth Santa Ynez CA

Geology

Geologically the mountains are young and mostly of

sedimentary Sedimentary rocks are types of rock formed by the cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or deposited at Earth's surface. Sedime ...

origin. The most common rock types in the range are sandstones and shales, with some limestone in the western portion of the range. Volcanic rocks can be found at the very western extremity of the range, near Point Arguello (Tranquillion Mountain Volcanics), while some

schist Schist ( ) is a medium-grained metamorphic rock generally derived from fine-grained sedimentary rock, like shale. It shows pronounced ''schistosity'' (named for the rock). This means that the rock is composed of mineral grains easily seen with a l ...

s of the Franciscan Assemblage are exposed in a number of locations. The Santa Ynez Mountains were uplifted in

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

time, beginning about five million years ago, along the

, a feature which is considered to be active. The left bend in the

San Andreas Fault The San Andreas Fault is a continental Fault (geology)#Strike-slip faults, right-lateral strike-slip transform fault that extends roughly through the U.S. state of California. It forms part of the tectonics, tectonic boundary between the Paci ...

is proposed to have constrained northward moving

lithosphere A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time ...

to cause uplift of the range. Being a young uplift, the slopes are steep and the topography is extremely rugged; the gradient is highest on the northern side above , adjacent to the trace of the fault. Dramatic sandstone formations, including outcrops of the resistant Coldwater and Matilija formations, are visible at many locations in the range.

Biology

The predominant ground cover is

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 ...

, with

coastal sage scrub Coastal sage scrub, also known as coastal scrub, CSS, or soft chaparral, is a low scrubland plant community of the California coastal sage and chaparral subecoregion, found in coastal California and northwestern coastal Baja California. It is ...

, oak woodland and grasslands at lower elevations. Isolated stands of conifers (mostly Coulter pines) and other evergreen trees such as

bay laurel ''Laurus nobilis'' is an aromatic evergreen tree or large shrub with green, glabrous (smooth) leaves. It is in the flowering plant family Lauraceae. According to Flora Cretica (Kleinsteuber Books, 2024, ISBN 978-3-9818110-5-6) the stem can be 1 ...

, tanbark oak and madrone grow on the higher parts of the northern slopes, which are cooler and shadier than the southern slopes exposed to the sun. At lower elevations on the southern side of the range, a virtually frost-free zone,

avocado The avocado, alligator pear or avocado pear (''Persea americana'') is an evergreen tree in the laurel family (Lauraceae). It is native to Americas, the Americas and was first domesticated in Mesoamerica more than 5,000 years ago. It was priz ...

s are grown in considerable quantity. The Santa Ynez Mountains are home to many species typical of the California chaparral and woodlands ecoregion, such as the Western fence lizard, Nuttall's woodpecker,

Steller's jay Steller's jay (''Cyanocitta stelleri'') is a bird native to western North America and the mountains of Central America, closely related to the blue jay (''C. cristata'') found in eastern North America. It is the only crest (feathers), crested jay ...

striped skunk The striped skunk (''Mephitis mephitis'') is a skunk of the genus ''Mephitis (genus), Mephitis'' that occurs across much of North America, including southern Canada, the United States, and northern Mexico. It is currently listed as least concern ...

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the North American, northern or common raccoon (also spelled racoon) to distinguish it from Procyonina, other species of raccoon, is a mammal native to North America. It is the largest ...

mule deer The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related whit ...

bobcat The bobcat (''Lynx rufus''), also known as the wildcat, bay lynx, or red lynx, is one of the four extant species within the medium-sized wild cat genus '' Lynx''. Native to North America, it ranges from southern Canada through most of the c ...

, and

coyote The coyote (''Canis latrans''), also known as the American jackal, prairie wolf, or brush wolf, is a species of canis, canine native to North America. It is smaller than its close relative, the Wolf, gray wolf, and slightly smaller than the c ...

. Large predator species include

mountain lion The cougar (''Puma concolor'') (, ''Help:Pronunciation respelling key, KOO-gər''), also called puma, mountain lion, catamount and panther is a large small cat native to the Americas. It inhabits North America, North, Central America, Cent ...

and black bear, the latter of which wanders in and out of the range within territories in excess of .

Inhabitants

Early inhabitants included the

Chumash people The Chumash are a Native Americans in the United States, Native American people of the central and southern coastal regions of California, in portions of what is now Kern County, California, Kern, San Luis Obispo County, California, San Luis O ...

who left behind many examples of

rock art In archaeology, rock arts are human-made markings placed on natural surfaces, typically vertical stone surfaces. A high proportion of surviving historic and prehistoric rock art is found in caves or partly enclosed rock shelters; this type al ...

including those at Painted Cave SHP. Large portions of the mountain range are now in the

, although there are private inholdings, including some substantial communities, such as the Painted Cave community where

Jane Fonda Jane Seymour Fonda (born December 21, 1937) is an American actress and activist. Recognized as a film icon, Jane Fonda filmography, Fonda's work spans several genres and over six decades of film and television. She is the recipient of List of a ...

owned the ridgetop Laurel Springs Ranch into the late 1990s. Other famous residents have included

Ronald Reagan Ronald Wilson Reagan (February 6, 1911 – June 5, 2004) was an American politician and actor who served as the 40th president of the United States from 1981 to 1989. He was a member of the Republican Party (United States), Republican Party a ...

, whose

Rancho del Cielo Rancho del Cielo is a ranch located atop the Santa Ynez Mountain range northwest of Santa Barbara, California. For more than 20 years, it was the vacation home of Ronald and Nancy Reagan. The ranch's Spanish name translates to Sky's Ranch or ...

is at the top of the range west of Santa Barbara, and Ben Adelson. The Cold Spring Tavern is a popular local gathering place beneath the Cold Spring Bridge. Santa ynez peak looking west

Climate

The climate of the mountain range is

. Summers are warm and almost entirely rainless, save for occasional

monsoon A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in Atmosphere of Earth, atmospheric circulation and precipitation associated with annu ...

al showers in August and September, though in most years there is no rain between May and October. Most of the higher coastal slopes of the range average between to almost of precipitation per year (mostly falling between November and March), about twice the total of the coastal plain below. About one year in three snow falls on the higher peaks in the mountains, but it rarely stays for longer than a few days. In the late spring and early summer the mountains and areas below to the south are subject to occasional intense sundowner winds, a type of

foehn wind A Foehn, or Föhn (, , , ), is a type of dry, relatively warm downslope wind in the lee of a mountain range. It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of its moisture on windw ...

in which the air is heated adiabatically and dried as it moves downslope. In dry years these winds pose an extreme fire hazard. Occasionally extremely destructive fires originate in the Santa Ynez Mountains. In June 1990, a fire which began near Painted Cave burned south into the city of Santa Barbara, driven by sundowner winds, destroying over 500 homes. A fire in the 1940s destroyed most of the mansion that is now called Knapp's Castle. More recent fires, such as the

Tea Tea is an aromatic beverage prepared by pouring hot or boiling water over cured or fresh leaves of '' Camellia sinensis'', an evergreen shrub native to East Asia which probably originated in the borderlands of south-western China and nor ...

and Jesusita fires, have also been destructive to properties.

Geography

Geology

Biology

Inhabitants

Climate

See also

References

Further reading