California County Routes in zone S


There are 34 routes assigned to the "S" zone of the California Route Marker Program, which designates county routes in California. The "S" zone includes county highways in Imperial, Orange, Riverside, San Diego, and Santa Barbara counties.

S1

County Route S1, also known as Sunrise Highway for a portion of its length, is a long county route located entirely in San Diego County, California. It begins at SR 94 near Barrett and moves northward across Interstate 8, just west of the Laguna Summit. This segment is also known as Buckman Springs Road. North of I-8, it is the Sunrise Scenic Byway, a National Forest Scenic Byway.
;Route description
The route begins at SR 94 near Barrett not far from the Mexican border. From there, it heads northward along Buckman Springs Road. Soon afterwards, it enters the Cleveland National Forest. When the road reaches Interstate 8, while Buckman Springs Road continues northeastward across the freeway, CR S1 continues in a northwest direction along Old Highway 80, the original alignment of U.S. Route 80 in California. It then closely parallels I-8 for several miles. Upon crossing the freeway at Laguna Junction, CR S1 separates from Old Highway 80 and becomes Sunrise Scenic Byway.
From Interstate 8, it begins its ascent into the Laguna Mountains. The route here was built along a cliff overlooking Pine Valley to its west. Around here, the vegetation still consists of chaparral and sagebrush. As the route gains elevation through Cleveland National Forest, the route becomes more heavily forested. Around here, numerous campgrounds dot the side of the road. There is a picnic area overlooking Anza-Borrego Desert State Park near the Burnt Rancheria Campground, which is often said to deeply contrast the forest scenery along the route. Upon passing the settlement of Laguna Mountain, the vegetation along the route mostly consists of dead trees devastated by the 2003 Cedar Fire.
As the route approaches its north end at SR 79, Lake Cuyamaca is visible. The north terminus is located just north of Cuyamaca Rancho State Park where it meets State Route 79.
;History
The route was established by the county in the year 1959, where the entire route was designated as it is now. No major numbering or routing changes occurred throughout its history. The northern segment of the route was also established as a Scenic Byway in 1959.

S2

County Route S2 is a county highway in the US state of California. It runs for, north–south, in Imperial County and San Diego County. S2 is the third longest county route in California and is almost exclusively a two-lane rural road. It largely follows the route of the former Southern Emigrant Trail and Butterfield Overland Mail.
;Route description
Starting at mile marker zero, the highway begins at a junction with State Route 79 near the community of Warner Springs. As it descends southeast toward the desert floor it becomes San Felipe Road until it crosses State Route 78 at Scissors Crossing in Shelter Valley. South of the 78, the name of the highway changes to the Great Southern Overland Stage Route of 1849, then further south, it forks at a remote junction with the historic dirt road to become to Sweeney Pass Road. East of the San Diego/Imperial County Line of this segment is also called Imperial Highway. The highway runs south through an interchange with Interstate 8 then ends at a junction with State Route 98 in Ocotillo, California.

S3

County Route S3 begins at a junction with State Route 78 and runs roughly north over Yaqui Pass to Borrego Springs, bearing the name Yaqui Pass Road. It turns left onto Deep Well Trail and left again onto Borrego Springs Road. It ends at a junction with County Route S22 called Christmas Circle. Its total length is.
There is one call box on this highway, located at Yaqui Pass summit.
The highway is part of the Juan Bautista de Anza National Historic Trail Auto Tour Route.

S4

County Route S4 is a road in the northern city limits of San Diego. The route traverses across Interstate 15 as Poway Road east to State Route 67.
The route's western terminus is at I-15, where the road continues west as Rancho Penasquitos Boulevard, traverses across SR 56, and finally ends as Carmel Mountain Road. Eastward, the road traverses through the city of Poway with the name Poway Road and has its east end at SR 67. Within Poway, it is one of the busiest streets in the city.
The route was established in 1959.

S5

County Route S5 is a road in both Poway, California and San Diego, California. Its south end is County Route S4, or Poway Road, and its north end is Interstate 15.
The road's south end is at County Route S4 in Poway. It winds north through Poway as Espola Road and then turns slightly west, ending at Interstate 15 as Rancho Bernardo Road.
The route was established in 1959.

S6

County Route S6 is a county route in San Diego County, California. It connects Del Mar with Palomar Mountain across San Diego County. It is one of a few San Diego County Routes with a discontinuity in its routing.
S6 starts at San Diego County Route S21 in Del Mar as Via de la Valle. It crosses Interstate 5 and meets with S8 in Rancho Santa Fe at the intersection of Via de la Valle and Paseo Delicias. At El Camino Del Norte the name changes to Del Dios Highway, past the community of Del Dios and into Escondido, California.
In Escondido, S6 runs along West and East Valley Parkways, to Valley Center Road through Valley Center, California. S6 ends at State Route 76.
About east on SR 76, S6 begins again as South Grade Road, which winds northward on Palomar Mountain. It intersects with S7, then continues north until it ends at the Palomar Observatory.
The route was defined in 1959.

S7

County Route S7 is a county route in San Diego County, California that provides access to Palomar Mountain.
;Route description
S7's western terminus is at State Route 76 east of Pauma Valley, California. It begins as a dirt road known as the Nate Harrison Grade. Then it returns to pavement as it ascends Palomar Mountain and meets San Diego County Route S6. It enters Palomar Mountain State Park. Then, it descends to end at SR 76 near Lake Henshaw.
Nate Harrison Grade is not signed as County Route S7, but it is a logical westward extension of the signed portion. With a 10% grade, it was the only road to the top of Palomar Mountain until the 1940s, when East Grade Road was built for the construction of the Palomar Observatory. The road was formerly known as "Nigger Nate Road", named after Nate Harrison, an early African-American homesteader. The name was changed in 1956 at the request of the NAACP.
On a small turnout is a monument to Gregory Pacheco and a good view to the north. According to a plaque at the monument, pictured below, Gregory Pacheco was a firefighter who died in the
La Jolla Fire in 1999. The descent on the eastern side of Palomar Mountain offers panoramic views of Lake Henshaw.

S8

County Route S8 exists mostly along Lomas Santa Fe Drive and Linea Del Cuelo in San Diego County, California. Its western end is County Route S21 in Solana Beach and its eastern end is at Via De La Valle in Rancho Santa Fe.
The route begins in Solana Beach at Old Highway 101. It winds eastward through San Diego County, crossing through Solana Beach and unincorporated San Diego County, and ends at Via De La Valle in Rancho Santa Fe. The last portion of the county road passes through Rancho Santa Fe on Paseo Delicias.
;Major intersections

S9

County Route S9, mostly known as Encinitas Boulevard, is a road in San Diego County, California. Its west end is at County Route S21 in Encinitas and it its east end is at Paseo Delicias in Rancho Santa Fe.
Once outside Encinitas, the county route follows portions of Rancho Santa Fe Road, La Bajada, Los Morros, and La Granada, before terminating at Paseo Delicias.
;Major intersections

S10

County Route S10, also known as Rancho Santa Fe Road, runs through North County in San Diego.
S10 begins at Encinitas Boulevard in Encinitas, heading in a generally northward direction. It enters Carlsbad and turns eastward. This road travels into San Marcos and passes near the unincorporated area of Lake San Marcos. Rancho Santa Fe Road intersects with San Marcos Boulevard and continues northward. There is a junction with State Route 78. A short distance north, Rancho Santa Fe ends at County Route S14.
;Major intersections

S11

County Route S11, known as El Camino Real, runs through North County in San Diego.
S11's southern terminus is Encinitas Boulevard in Encinitas. It continues northward through Encinitas, intersecting with Lecuadia Boulevard/Olivenhain Road, which leads to County Route S10 east of this intersection. After this point, it enters Carlsbad, where it intersects with Palomar Airport Road. It continues northward through Carlsbad, ending at State Route 78 in Oceanside.
Note that El Camino Real continues for several miles beyond both termini. It extends southward through Encinitas until it reaches San Elijo Lagoon and ends at Manchester Avenue. An unconnected road further east also called El Camino Real starts at the San Elijo Lagoon and continues south for several miles until Carmel Mountain Road. Northward in Oceanside, El Camino Real passes under State Route 76 and ends just north at Douglas Drive.
;Major intersections

S12

County Route S12, also known as Palomar Airport Road, San Marcos Boulevard, Twin Oaks Valley Road, and Deer Springs Road, runs through North County in San Diego.
S12's western terminus is at Carlsbad Blvd in Carlsbad. Almost immediately after it begins, S12 intersects with Interstate 5. It passes Legoland California and continues eastward, passing its namesake, McClellan–Palomar Airport. It intersects with El Camino Real before running through a number of industrial and business parks. Eventually, County Route S12 enters San Marcos, where it is renamed San Marcos Boulevard after an intersection with Business Park Drive. San Marcos Boulevard intersects Rancho Santa Fe Rd and continues eastward, crossing State Route 78. Shortly thereafter, San Marcos Blvd intersects with Twin Oaks Valley Road, which bears the S12 designation after this junction. Shortly after becoming S12, Twin Oaks Valley Road passes over Mission Rd without actually intersecting it, then continues to the northern borders of San Marcos. At the edge of the city, Twin Oaks Valley Road narrows into a private road, and S12 bears right to become Deer Springs Road, which continues northward through unincorporated land. Eventually the road turns east, and S12 ends at an interchange with Interstate 15, though the road itself continues as Mountain Meadow Road through Hidden Meadows.
The route was established in 1961.

S13

County Route S13, also known as Vista Village Drive, East Vista Way, and Mission Road, runs through North County in San Diego. It is distinctive for having a three-mile discontinuity in Bonsall.
S13's southern terminus is at SR 78 in Vista, where the street is known as Vista Village Drive. This section of S13 is the northern boundary of the newly renovated downtown area of Vista, and in this area the road intersects with Santa Fe Avenue, which is San Diego County Route S14. Shortly afterwards, the road's name changes to East Vista Way, and continues northward outside the city limits into the unincorporated community of Bonsall.
S13 is unusual in that, according to official legislation, its route is discontinuous. In Bonsall, East Vista Way meets SR 76 and, from this point, loses its status as Route S13. Nearly three miles northeast on SR 76, S13 begins again, continuing northward, but as South Mission Road.
Mission Road cuts north through Bonsall and passes the neighborhoods of San Luis Rey Heights and Winterwarm before entering Fallbrook. In Fallbrook, South Mission Road splits off into South Main Avenue, which carries the S13 signage. These two streets run parallel to each other for several blocks; East Fallbrook Rd begins at Mission and intersects Main. After a short distance, Mission turns east, intersecting Main; Mission then continues as S13. S13 continues eastward, ending at an interchange with Interstate 15.
Almost all of S13, except for later realigned portions, is an old alignment of U.S. Route 395, and Historic Route signs are posted in unincorporated areas.
The route was established in 1968.

S14

County Route S14, also known as Santa Fe Avenue and Mission Road, runs through North County in San Diego.
S14's western terminus is at State Route 76 in Oceanside, where it is known as North Santa Fe Avenue. It travels into Vista, becoming South Santa Fe Avenue before intersecting with County Route S13, or Vista Village Drive, in downtown Vista. At this point it begins to run parallel to State Route 78, which it does until its terminus. Santa Fe travels into western San Marcos, where it intersects with County Route S10 ; it is at this intersection that Santa Fe becomes Mission Road. Mission continues through San Marcos, passing under Twin Oaks Valley Road without an intersection. In eastern San Marcos, Mission Road crosses State Route 78 without an intersection and becomes Mission Avenue. Shortly afterward, it enters Escondido, where it crosses Interstate 15, again with no intersection. Shortly after this point, the freeway portion of SR 78 ends and that route turns right onto Broadway; S14 intersects with and ends at Broadway.
S14 east of S13, except for later realigned portions, is an old alignment of U.S. Route 395, and Historic Route signs are posted in unincorporated areas.
The route was established in 1968.

S15

County Route S15 is a county route in San Diego County, California. Its west end is County Route S13 and its east end is at Interstate 15.
S15's western terminus is at County Route S13, also known as Mission Road, in Fallbrook. S15 begins as East Fallbrook Street. At the intersection with South Stage Coach Lane, S15 continues south to the intersection with Reche Road, at which point S15 again heads east. S15 continues east as Reche Road until the intersection with Old Highway 395, adjacent to Interstate 15.
The route was established in 1959.

S16

County Route S16, also known as Pala-Temecula Road, Pala Road, and Pechanga Parkway, is a county route in San Diego County and Riverside County, California. Its south end is SR 76 and its north end is SR 79.
The route's southern terminus is at SR 76 on the Pala Indian Reservation, in the San Luis Rey River Valley, near the community of Pala. It twists through a short but rugged and steep mountain range and continues northward as Pala-Temecula Road through rural San Diego County.
When it crosses the Riverside County line and enters the Pechanga Indian Reservation, it becomes Pala Road. Shortly thereafter, County Route S16 widens to four lanes as it reaches the city limits of Temecula, where it becomes Pechanga Parkway. Near the Pechanga Resort & Casino, Pechanga Parkway becomes a six-lane arterial road and continues along several large suburban neighborhoods before ending at a T intersection with SR 79. The portion of County Route S16 known as Pechanga Parkway, as well as the portion of SR 79 known as Temecula Parkway, are unsigned because the City of Temecula maintains jurisdiction over both segments.
The route was established in 1959.

S17

County Route S17 runs through San Diego County, connecting Chula Vista and El Cajon. The route consists of portions of several roads passing through the cities of Chula Vista and El Cajon, and the unincorporated communities of Bonita, Spring Valley, and Rancho San Diego.
County Route S17 roughly parallels State Route 54 from Interstate 5 east to State Route 125, running along E Street, Bonita Road, Sweetwater Road, South Worthington Street, and Paradise Valley Road. The route then shares the same alignment as State Route 54, from State Route 125 northeast to the El Cajon city limit, running along Jamacha Boulevard, Campo Road, and Jamacha Road. Within El Cajon, County Route S17 shares the same alignment as the former State Route 54, continuing north to Interstate 8 along Jamacha Road and 2nd Street.
The portions of County Route S17 within the cities of Chula Vista and El Cajon are no longer signed. The portions of the route within Bonita and Spring Valley are signed. However, all signs in Rancho San Diego appear to have been removed except for the one heading east coming from the terminus of the freeway portion of State Route 94. In El Cajon city limits, the route is signed with Business Route 54.
The route was established in 1964.

S18

County Route S18 is a county highway in the US state of California in Orange County. The route follows El Toro Road and Santiago Canyon Road which proceeds in a boomerang-like pattern from State Route 133 in Laguna Beach to State Route 55 near Orange. CR S18 traverses as a loop around the urban areas of Orange County and cuts through the Santa Ana Mountains. The road is one of four county routes in Orange County that are signed in areas nearby the route, such as southbound Interstate 5 and southbound State Route 133. It is also noted to be the longest county route in Orange County and is the only major route that allows motorists to drive through, in, and out of the Santa Ana Mountains.
The Santiago Canyon Road portion of CR S18 in the Santa Ana Mountains is planned to become designated as an official scenic highway as part of the State Scenic Highway System. This makes it the second highway to become designated as a scenic road in Orange County, California, despite the impact from the Santiago Fire as part of the wildfires in October 2007.
;Major intersections
The entire route is in Orange County.

S19

County Route S19 is a county highway in the US state of California in Orange County. The route follows Live Oak Canyon Road from O'Neill Park to El Toro Road to Trabuco Canyon.
County Route S19 is notorious for many fatal accidents that have occurred in the recent years since 2000, and many lost lives due to such accidents.
The route was established in 1961.

S20

County Route S20 is a former county highway in the US state of California. As the only county route in Santa Barbara County, it was merged with State Route 1 in 1988 making the southbound SR 1 freeway to go along with Country Route S20 to Vandenberg AFB.

S21

County Route S21 is a south–north running road serving the coastal communities of northern San Diego County, running from San Diego in the south to Oceanside in the north. The route is signed in many places as "Historic Route 101" with the official Historic U.S. 101 shields. S21 follows the prior alignment of U.S. Route 101 through this region. The route is also called "Coast Highway" in some places as well. This route was originally designated in 1968 and is long.
;Route description
County Route S21 begins at Interstate 5 in the north of San Diego as Genesee Avenue. After proceeding west-northwest for 3/4 mile it intersects Torrey Pines Road and continues north with that name, providing access to the Torrey Pines State Natural Reserve. The road then travels north into Del Mar, where it is renamed "Camino Del Mar". While in Del Mar the route passes both the historic Del Mar Racetrack and through the historic downtown of Del Mar. In Solana Beach the route moves closer to the coast. Along this stretch, it is named "Highway 101" and the city has signed the route along its length with faux U.S. Highway shields that resemble the official U.S. 101 shields in use today along with the state issued Historic 101 shield. While to the north in Encinitas the route's name becomes "Coast Highway 101" also in homage to the old U.S. Route. In Carlsbad it becomes "Carlsbad Boulevard”. The route is named "Coast Highway" in Oceanside, and comes to an end at Interstate 5 just south of Camp Pendleton.
The section of this road between La Costa Avenue and Palomar Airport Road was once known as the . The majority of the route from the Del Mar city limits to State Route 76 in Oceanside is signed as Historic U.S. 101, and is also an unsigned Business Route Interstate 5.
;Major intersections

S22

County Route S22 begins at a junction with County Highway S2 in San Diego County and runs eastward as Montezuma Valley Road through the rural community of Ranchita. It enters Anza-Borrego Desert State Park and then descends for approximately to the desert community of Borrego Springs, offering magnificent views of the Borrego Valley as it winds steeply down Montezuma Grade.
As it enters Borrego Springs, the highway turns right onto Palm Canyon Drive. In the middle of Borrego Springs, it passes through the only large traffic circle in San Diego County.
It continues east, changes its name to the Borrego-Salton Seaway, enters Imperial County, runs through Anza-Borrego State Park and ends at a junction with State Route 86 in Salton City, a community on the shore of the Salton Sea.
The route was established in 1968.

S24

County Route S24 is a county highway in the US state of California in southeast Imperial County, California. It is north, across the Colorado River and adjacent to Yuma, Arizona, serving the city of Winterhaven. The southern two-thirds of the route travels through the Quechan Indian Tribal lands of the Fort Yuma Indian Reservation.

Route description

The route begins from Winterhaven, California, adjacent to the eastern exit of Interstate 8 in California at Winterhaven. The route travels northeast through portions of eastern Winterhaven, then immediately turns north through farmland, for ;. The route turns east then north, east, then north on a newly paved stretch through farmland in the Bard area for. The final turn east is through farmland for then a northeast stretch along the western shoreline of the Colorado River, Laguna Dam and a terminus at the turn-off to Imperial Dam; the river stretch is about, and seasonally has osprey, phainopepla, Abert's towhee, belted kingfisher, double-crested cormorant, and everpresent Gambel's quail, plus numerous other bird species, including the water birds. Of note, the osprey have snag perches along the river route, and can be seen eating fish on pole tops, towers, etc.
The terminus at the Laguna Dam turn-off transitions into the extension westwards in southwest Arizona from U.S. 95 in Arizona, westwards on Imperial Dam Road of Yuma County, Arizona and the US Army Yuma Proving Ground.
No traffic lights occur on the route. Only one stop sign is encountered while traveling north to south; that one 4-way stop is encountered at about 1.7 miles north of Winterhaven. south of the Imperial Dam entrance, the Ferguson Lake Road and the Senator Wash access exits to the northwest. The eastern access points to the Little Picacho Wilderness can be found along the northern sections of Ferguson Lake Road.
The route was established in 1970.
Route S24 serves as a second access route to the Yuma Proving Ground, and also to the main housing and administration center of YPG. The route is also the main access to the housing facilities in the Imperial Dam region, administered by the Bureau of Land Management; the Imperial Dam housing region is on the Arizona side of the Colorado River.

S25

S26

S27

S28

S29

S30

S31

S32

S33

S34

S34 is a road connecting the California State Route 78 portion between Blythe, California and Brawley, California to Interstate 8 near Felicity, California and west of Yuma, Arizona. Located in the Yuma Desert and close to the Algodones Dunes, the road also goes through Ogilby, California.

S78

County Route S78 is a former routing of SR 78.

S80

County Route S80 is a county route in Imperial County, California. It was once a portion of U.S. Route 80, which no longer enters the state. S80 travels through Imperial County for to the vicinity of the Colorado River near Yuma, Arizona.

Route description

S80 begins in the west at the junction of S80 and Imperial County Route S2 as the Evan Hewes Highway roughly paralleling the routing of Interstate 8. This portion of the highway travels east to El Centro.
In downtown El Centro, S80 becomes Adams Avenue. At Imperial Avenue, S80 junctions with State Route 86 from the north and Business Loop I-8 from the south. The roads run concurrent down Adams Avenue, and all three turn south along 4th Street. S80 then turns to the east along Main Street which takes it out of El Centro while State Route 86 and Business I-8 continue south. Outside of El Centro after its junction with Imperial County Route S31, S80 resumes the designation of Evan Hewes Highway. S80 also intersects State Route 111 along this stretch. S80 continues east until it reaches its terminus at the junction with State Route 115. State Route 115 continues along the Evan Hewes Highway and old U.S. Route 80.

History

U.S. Route 80 was deleted from California legislatively in 1964, though it would be another ten years before all the U.S. Highway signage was removed from the route. S80 was defined in 1973 shortly before the last Route 80 signs had been taken down.
In 2006, the California legislature, as part of concurrent resolution ACR 123, made the former Route 80, including County Route S80, an official historic route.
For the short distance S80 runs concurrent with SR 86 it is part of the Juan Bautista de Anza National Historic Trail. This trail runs along the route Juan Bautista de Anza took along his expedition into California from 1775–76.