The Sierra Pelona, also known as the Sierra Pelona Ridge or the Sierra Pelona Mountains and originally known as the Liebre Mountains, is a mountain ridge in 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 ...

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural List of regions of California, region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal reg ...

. Located in northwest

Los Angeles County Los Angeles County, officially the County of Los Angeles and sometimes abbreviated as LA County, is the most populous county in the United States, with 9,663,345 residents estimated in 2023. Its population is greater than that of 40 individua ...

, the ridge is bordered on the north by 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 ...

and lies within and is surrounded by the

Angeles National Forest The Angeles National Forest (ANF) of the United States Forest Service is located in the San Gabriel Mountains and Sierra Pelona Mountains, primarily within Los Angeles County in Southern California. The ANF manages a majority of the San Gabri ...

and a tiny section in the Los Padres National Forest

Geography

The Sierra Pelona Mountains lie northwest of the

San Gabriel Mountains The San Gabriel Mountains () are a mountain range located in Los Angeles and San Bernardino counties, California, United States. The mountain range is part of the Transverse Ranges and lies between the Los Angeles Basin and the Mojave Desert ...

, which are divided by the wide Soledad Canyon formation. The mountains are flanked to the south by the Santa Clarita Valley and separated from the

Antelope Valley The Antelope Valley is a valley primarily located in northern Los Angeles County, California, United States and the southeast portion of Kern County, California, Kern County, and constitutes the western tip of the Mojave Desert. It is situated ...

and the

Mojave Desert The Mojave Desert (; ; ) is a desert in the rain shadow of the southern Sierra Nevada mountains and Transverse Ranges in the Southwestern United States. Named for the Indigenous peoples of the Americas, indigenous Mohave people, it is located pr ...

to the north by the

. Toward the southeast lie Vasquez Rocks, thrust up by the fault. Toward the west lies

Interstate 5 Interstate 5 (I-5) is the main north–south Interstate Highway System, Interstate Highway on the West Coast of the United States, running largely parallel to the Pacific coast of the contiguous U.S. from Mexico to Canada. It travels thro ...

, Pyramid Lake, and the Los Padres National Forest. The range has a small extension west of I-5. The Tejon Pass separates the Sierra Pelonas, the San Emigdios, the Tehachapis, and 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 ...

near Gorman and Lebec. Within the Sierra Pelonas lie the rural areas of Neenach, Three Points, Lake Hughes, Elizabeth Lake, Acton, Agua Dulce and Green Valley. The cities of Santa Clarita, Palmdale, and Lancaster are located at the base of the mountains.

Climate

The climate of the mountains is a

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 ...

. Summers are mostly dry except for occasional thunderstorms, and winters comparatively cold and wet. Snowfall is infrequent due to the relatively low elevations of mountains within this ridge, with only the few tallest peaks regularly receiving snowfall during the winter.

Ecology

Mainly the ridge falls under the California montane chaparral and woodlands ecoregion, excepting the northeastern flank's gradual slope into the

near Palmdale where the ecology transitions to that of the

. The mountains are primarily covered in short grasses, scrub oak trees,

yucca ''Yucca'' ( , YUCK-uh) is both the scientific name and common name for a genus native to North America from Panama to southern Canada. It contains 50 accepted species. In addition to yucca, they are also known as Adam's needle or Spanish-bayon ...

, and other

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 ...

shrubs. The ridge is prone to wildfires in the summer and fall, especially when the Santa Ana winds blow in from the Antelope Valley.

Hydrology

Three major tributaries of the Santa Clara River and numerous minor watercourses and washes drain the ridge:

Castaic Creek Castaic Creek (Chumashan languages, Chumash: ''Kaštiq'') is a , accessed March 16, 2011 stream in the Sierra Pelona Mountains, in northeastern Los Angeles County, California. It is a tributary of the Santa Clara River (California), Santa Clar ...

, San Francisquito Creek, and Bouquet Creek. Three sag ponds nestle within the narrow valley that divides the mountains from the Antelope Valley: Hughes Lake, Munz Lakes, and Elizabeth Lake.

Human history

Native American habitation

The Native population of California in the Sierra Pelona and Santa Susana Mountains included the Tataviam and Serrano people. They traded with the

Tongva The Tongva ( ) are an Indigenous peoples of California, Indigenous people of California from the Los Angeles Basin and the Channel Islands of California, Southern Channel Islands, an area covering approximately . In the precolonial era, the peop ...

and Chumash to the south and west, until the

Spanish colonization of the Americas The Spanish colonization of the Americas began in 1493 on the Caribbean island of Hispaniola (now Haiti and the Dominican Republic) after the initial 1492 voyage of Genoa, Genoese mariner Christopher Columbus under license from Queen Isabella ...

relocated them from their homelands.

18th and 19th centuries

The San Francisquito Canyon, which runs north-south through the mountains, served as a major wagon route between the Antelope and San Fernando Valleys. This corridor summited at San Francisquito Pass and was part of the El Camino Viejo - an alternate land route to the El Camino Real for reaching northern Spanish and Mexican colonial Alta California - as well as the

Butterfield Overland Mail Butterfield Overland Mail (officially Overland Mail Company)Waterman L. Ormsby, edited by Lyle H. Wright and Josephine M. Bynum, "The Butterfield Overland Mail", The Huntington Library, San Marino, California, 1991. was a stagecoach service in ...

route.

20th century

The Ridge Route, a landmark two-lane highway that connected

Los Angeles Los Angeles, often referred to by its initials L.A., is the List of municipalities in California, most populous city in the U.S. state of California, and the commercial, Financial District, Los Angeles, financial, and Culture of Los Angeles, ...

to the rest of California, was built along the western flank of the ridge and was completed in 1915. It was later bypassed by the Ridge Route Alternate ( US 99) in 1930, itself superseded by

completed in 1971. The rapid development of

throughout the 20th century saw construction of the

Los Angeles Aqueduct The Los Angeles Aqueduct system, comprising the Los Angeles Aqueduct (Owens Valley aqueduct) and the Second Los Angeles Aqueduct, is a water conveyance system, built and operated by the Los Angeles Department of Water and Power. The Owens Valley ...

and five separate reservoirs to supply water to the region:

Castaic Lake Castaic Lake (Chumashan languages, Chumash: ''Kaštiq'') is a reservoir formed by Castaic Dam on Castaic Creek, in the Sierra Pelona Mountains of northwestern Los Angeles County, California, United States, near the town of Castaic, California, C ...

, Bouquet Reservoir, Drinkwater Reservoir, Pyramid Lake and Dry Canyon Reservoir and the St. Francis Reservoir, both now drained and destroyed.

Highest peaks

* Burnt Peak: 5,788 ft (1,764 m) * Liebre Mountain: 5,760+ ft (1,756+ m) * Sawmill Mountain: 5,514 ft (1,681 m) * Little Burnt Peak: 5,499 ft (1,676 m) * Sierra Pelona: 5,220 ft (1,591 m) * Sawtooth Mountain: 5,200 ft (1,585 m) * Mount McDill: 5,177 ft(1,578 m) * Grass Mountain: 4,606 ft (1,404 m) * Redrock Mountain: 4,501 ft (1372 m) * Jupiter Mountain: 4,498 ft (1,371 m) * Whitaker Peak: 4,151 ft (1,265 m) * Warm Springs Mountain: 4,019 ft (1,225 m) * Redrock Mountain (benchmark): 3,991 ft (1,216 m) * Reservoir Summit: 3,980 ft (1213 m) * Townsend Peak: 3,184 ft (970 m)

Adjacent landforms

* Tehachapi Mountains - on the north *

San Emigdio Mountains The San Emigdio Mountains are a part of the Transverse Ranges in Southern California, extending from Interstate 5 at Lebec and Gorman on the east to Highway 33–166 on the west. They link the Tehachapis and Temblor Range and form the southe ...

- on the northwest *

- on the west * Santa Susana Mountains - to the southwest *

- to the east * Santa Clarita Valley - to the south * Soledad Canyon - to the southeast *

(part of the

) - on the east-northeast