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 highway located entirely in San Diego County, California, United States. It begins at State Route 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 Mount Laguna, the vegetation along the route mostly consists of dead trees devastated by the 2003 Cedar Fire. The route continues through the Anza-Borrego Desert State Park.
As the route approaches its north end at State Route 79, Lake Cuyamaca is visible. The north terminus is located just north of Cuyamaca Rancho State Park where it meets SR 79.
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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.
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S2
County Route S2 is a county highway in the U.S. state of California. It runs for, north–south, in Imperial County and San Diego County. CR 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 SR 78, the name of the highway changes to the Great Southern Overland Stage Route of 1849. It passes through Blair Valley, Canebrake Canyon, Vallecito, and Agua Caliente. Further south, it forks at a remote junction with the historic dirt road to become to Sweeney Pass Road. Sweeney Pass is located between the Volcanic Hills and the Coyote Mountains. 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 near Ocotillo.
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S3
County Route S3 is a county highway in San Diego County, California, United States. It 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 at a large roundabout known as 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.
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S4
County Route S4 is a road in San Diego County, California, United States, in the northern city limits of San Diego and in the city of Poway. The route is traversed entirely by Poway Road from Interstate 15 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 as 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.
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S5
County Route S5 is a road in San Diego County, California, United States, in Poway and San Diego. It runs from its southern end at Poway Road in Poway to its northern end at Interstate 15 in San Diego.;Route description
The road's south end is at Poway Road 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.
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S6
County Route S6 is a county highway in San Diego County, California, United States. 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.;Route description
CR S6 starts at CR S21 in Del Mar as Via de la Valle. It crosses Interstate 5 and meets with CR 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.
In Escondido, CR S6 runs along West and East Valley Parkways, to Valley Center Road through Valley Center. CR S6 ends at State Route 76.
About east on SR 76, CR S6 begins again as South Grade Road, which winds northward on Palomar Mountain. It intersects with CR S7, then continues north until it ends at the Palomar Observatory.
The route was defined in 1959.
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S7
County Route S7 is a county highway in San Diego County, California, United States, that provides access to Palomar Mountain.;Route description
CR 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.
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S8
County Route S8 is a county highway, mostly along Lomas Santa Fe Drive and Linea Del Cielo, in San Diego County, California, United States. Its western end is CR S21 in Solana Beach and its eastern end is at Via De La Valle in Rancho Santa Fe.;Route description
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.
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S9
County Route S9, mostly known as Encinitas Boulevard, is a road in San Diego County, California, United States. Its west end is at CR S21 in Encinitas and 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.
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S10
County Route S10, known entirely as Rancho Santa Fe Road, is a road in San Diego County, California, United States, that runs through the North County region of San Diego County.;Route description
CR 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.
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S11
County Route S11, known entirely as El Camino Real, is a county route in San Diego County, California, United States. It runs through the North County region in San Diego County, from Encinitas Boulevard in Encinitas to State Route 78 in Oceanside. As its street name implies, it is part of the 600-mile commemorative route connecting the 21 Spanish missions in California.;Route description
CR S11's southern terminus is Encinitas Boulevard in Encinitas. It continues northward through Encinitas, intersecting with Lecuadia Boulevard/Olivenhain Road, which leads to CR 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.
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