California State Route 23
Encyclopedia
State Route 23 is a state highway
in the U.S. state of California. The route runs roughly from Fillmore
to Malibu. This route is part of the California Freeway and Expressway System
.
Route 23 consists of three distinct sections. The southern section begins as Decker Canyon Road near Trancas in Malibu, where Route 23 intersects with the Pacific Coast Highway (State Route 1), or "PCH." This portion provides numerous beautiful vistas of the Santa Monica Mountains
and the Pacific Ocean during daytime, but extreme caution is advisable, especially as the road nears PCH. It is a notoriously dangerous road, and the rusted chassis of cars that have gone over the side can still be seen. Former Bassist Philip Taylor Kramer
who was with the rock band Iron Butterfly
from 1974-1977 allegedly committed suicide by driving his van over the side along this route. During its steep and winding path through the Santa Monica Mountains
as an increasingly windy canyon road until its intersection with Potrero Road, Route 23 becomes Westlake Boulevard, where it departs Los Angeles County
for Ventura County
and heads roughly two miles northeast through the Westlake section of Thousand Oaks
, a developed residential community. SR 23 then merges with the Ventura Freeway (U.S. Route 101) and runs concurrently with it north to the Moorpark Freeway.
The middle section, known as the Moorpark Freeway, is a major route for traffic headed between Thousand Oaks and Moorpark
. It starts in Thousand Oaks, splitting off from the concurrency with Route 101 and heading north, with three lanes in both directions. The Moorpark Freeway terminates at the exit for Los Angeles Avenue when the freeway turns east to become the Ronald Reagan Freeway (State Route 118). Funding for widening of the freeway was approved August 18, 2005, with construction to begin in February 2006, to be completed in 2009. The widening was completed ahead of schedule in April 2008. Officially, this portion is named the Military Intelligence Memorial Freeway, in honor of the U.S. 100th Infantry Battalion
and 442nd Regimental Combat Team
, composed entirely of Japanese American
s. Traffic along this freeway during rush hour
is extremely congested, particularly near the intersection with the 101.
The northernmost section begins at State Route 118
in Moorpark (called Los Angeles Avenue in Moorpark), and heads north as Grimes Canyon Road through orange groves and sandstone cliffs. In Fillmore
, it terminates at State Route 126. The road in Fillmore actually continues past Route 126 up to the foot of the Los Padres National Forest
.
On the SR 23 from Tierra Rejada Road and Olsen Road (and vice versa) is a bike lane. After crossing Tierra Rejada Road (going North) and Olsen Road (going South), bicyclists are prohibited from crossing.
, although it still ran concurrently with U.S. 101, which was then an expressway.
SR 23 was designated as part of the Freeway and Expressway System in 1959.
. The freeway was part of a 1958 plan by the Metropolitan Engineering Board, but was later considered to be geographically improbable and the plans were abandoned.
The freeway's southern portion, from CA 1 to US 101, follows the general alignment of Decker Canyon Road and Westlake Blvd, a segment of CA 23. It would continue north before terminating at CA 118 near First Street.
{| class=wikitable
!County
!Location
!Postmile
!Exit
!Destinations
!Notes
|-
|Los Angeles
LA 0.00-8.90
|Malibu
|0.00
|
|
|
|-
|rowspan=18|Ventura
VEN 0.00-24.17
|rowspan=12|Thousand Oaks
|T1.49
|
|Portrero Road – Hidden Valley
|
|-
|R2.26
|
|Triunfo Canyon Road
|
|-
|R2.88
|
|Agoura Road, Hampshire Road
|
|-bgcolor=#ddffdd
|R3.32
0.70Indicates that the postmile represents the distance along US 101 rather than SR 23.
|
|
|Interchange; south end of US 101 overlap
|-
|colspan=4 align=center|South end of freeway on US 101
|-
|1.62
|41
|Hampshire Road
|
|-bgcolor=#ddffdd
|3.11
R3.34
|12B
|
|North end of US 101 overlap; no exit number northbound
|-bgcolor=#ffdddd
|R3.70
|13
|Hillcrest Drive, Thousand Oaks Boulevard – Thousand Oaks
|Southbound exit and northbound entrance
|-
|R5.06
|14
|Janss Road
|
|-
|R6.03
|15
|Avenida de los Arboles
|
|-
|R7.17
|16
|Sunset Hills Boulevard
|
|-
|R8.21
|17
|Olsen Road – Simi Valley
|
|-
|rowspan=4|Moorpark
|R10.16
|19
|Tierra Rejada Road
|
|-
|colspan=4 align=center|North end of freeway
|-bgcolor=#ddffdd
|R11.43
T18.21Indicates that the postmile represents the distance along SR 118
rather than SR 23.
|20B
|
|Interchange; south end of SR 118 overlap
|-bgcolor=#ddffdd
|R17.49
R12.90
|
|
|North end of SR 118 overlap
|-
|rowspan=2|Fillmore
|24.17
|
|
|
|-
|24.17
|
|A Street
|Continuation beyond SR 126
State highway
State highway, state road or state route can refer to one of three related concepts, two of them related to a state or provincial government in a country that is divided into states or provinces :#A...
in the U.S. state of California. The route runs roughly from Fillmore
Fillmore, California
Fillmore is a city in Ventura County, California, United States. The population was 15,002 at the 2010 census, up from 13,643 at the 2000 census.- History :...
to Malibu. This route is part of the California Freeway and Expressway System
California Freeway and Expressway System
The California Freeway and Expressway System is a system of existing or planned freeways and expressways in the U.S. state of California. It is defined by the Streets and Highways Code.-List of roads in the system:*State Route 1 *State Route 2...
.
Route description
Route 23 is known as the Military Intelligence Service Memorial Highway from US 101 to California Route 118.Route 23 consists of three distinct sections. The southern section begins as Decker Canyon Road near Trancas in Malibu, where Route 23 intersects with the Pacific Coast Highway (State Route 1), or "PCH." This portion provides numerous beautiful vistas of the Santa Monica Mountains
Santa Monica Mountains
The Santa Monica Mountains are a Transverse Range in Southern California, along the coast of the Pacific Ocean in the United States.-Geography:...
and the Pacific Ocean during daytime, but extreme caution is advisable, especially as the road nears PCH. It is a notoriously dangerous road, and the rusted chassis of cars that have gone over the side can still be seen. Former Bassist Philip Taylor Kramer
Philip Taylor Kramer
Philip Taylor Kramer was a bass guitar player for the rock group Iron Butterfly during the 1970s. After this he obtained a night school degree in aerospace engineering, worked on the MX missile guidance system for a contractor of the US Department of Defense and later in the computer industry on...
who was with the rock band Iron Butterfly
Iron Butterfly
Iron Butterfly is a US psychedelic rock band best known for the 1968 hit "In-A-Gadda-Da-Vida".Their heyday was the late 1960s, but the band has been reincarnated with various members. In-A-Gadda-Da-Vida is the 31st best-selling album in the world, selling more than 25 million copies.-History:The...
from 1974-1977 allegedly committed suicide by driving his van over the side along this route. During its steep and winding path through the Santa Monica Mountains
Santa Monica Mountains
The Santa Monica Mountains are a Transverse Range in Southern California, along the coast of the Pacific Ocean in the United States.-Geography:...
as an increasingly windy canyon road until its intersection with Potrero Road, Route 23 becomes Westlake Boulevard, where it departs Los Angeles County
Los Angeles County, California
Los Angeles County is a county in the U.S. state of California. As of 2010 U.S. Census, the county had a population of 9,818,605, making it the most populous county in the United States. Los Angeles County alone is more populous than 42 individual U.S. states...
for Ventura County
Ventura County, California
Ventura County is a county in the southern part of the U.S. state of California. It is located on California's Pacific coast. It is often referred to as the Gold Coast, and has a reputation of being one of the safest populated places and one of the most affluent places in the country...
and heads roughly two miles northeast through the Westlake section of Thousand Oaks
Thousand Oaks, California
Thousand Oaks is a city in southeastern Ventura County, California, in the United States. It was named after the many oak trees that grace the area, and the city seal is adorned with an oak....
, a developed residential community. SR 23 then merges with the Ventura Freeway (U.S. Route 101) and runs concurrently with it north to the Moorpark Freeway.
The middle section, known as the Moorpark Freeway, is a major route for traffic headed between Thousand Oaks and Moorpark
Moorpark, California
Moorpark is a city in Southern California. It was founded in 1900 by Robert Poindexter, presumably named after the moorpark apricots that grew in the area. The city has experienced a great amount of growth since the late 1970s...
. It starts in Thousand Oaks, splitting off from the concurrency with Route 101 and heading north, with three lanes in both directions. The Moorpark Freeway terminates at the exit for Los Angeles Avenue when the freeway turns east to become the Ronald Reagan Freeway (State Route 118). Funding for widening of the freeway was approved August 18, 2005, with construction to begin in February 2006, to be completed in 2009. The widening was completed ahead of schedule in April 2008. Officially, this portion is named the Military Intelligence Memorial Freeway, in honor of the U.S. 100th Infantry Battalion
U.S. 100th Infantry Battalion
The 100th Infantry Battalion was a unit within the US Army's 34th Infantry Division during World War II. The primarily Nisei battalion was composed largely of former members of the Hawaii Army National Guard...
and 442nd Regimental Combat Team
442nd Regimental Combat Team
The 442nd Regimental Combat Team of the United States Army, was composed of Japanese-American enlisted men and mostly Caucasian officers. They fought primarily in Europe during World War II, beginning in 1944. The families of many of its soldiers were subject to internment...
, composed entirely of Japanese American
Japanese American
are American people of Japanese heritage. Japanese Americans have historically been among the three largest Asian American communities, but in recent decades have become the sixth largest group at roughly 1,204,205, including those of mixed-race or mixed-ethnicity...
s. Traffic along this freeway during rush hour
Rush hour
A rush hour or peak hour is a part of the day during which traffic congestion on roads and crowding on public transport is at its highest. Normally, this happens twice a day—once in the morning and once in the evening, the times during when the most people commute...
is extremely congested, particularly near the intersection with the 101.
The northernmost section begins at State Route 118
California State Route 118
State Route 118 is a state highway in the U.S. state of California that begins running west to east through Ventura and Los Angeles counties in southern California. It travels from Saticoy in Ventura County east to Lake View Terrace in Los Angeles...
in Moorpark (called Los Angeles Avenue in Moorpark), and heads north as Grimes Canyon Road through orange groves and sandstone cliffs. In Fillmore
Fillmore, California
Fillmore is a city in Ventura County, California, United States. The population was 15,002 at the 2010 census, up from 13,643 at the 2000 census.- History :...
, it terminates at State Route 126. The road in Fillmore actually continues past Route 126 up to the foot of the Los Padres National Forest
Los Padres National Forest
Los Padres National Forest is a forest located in southern and central California, which includes most of the mountainous land along the California coast from Ventura to Monterey, extending inland...
.
On the SR 23 from Tierra Rejada Road and Olsen Road (and vice versa) is a bike lane. After crossing Tierra Rejada Road (going North) and Olsen Road (going South), bicyclists are prohibited from crossing.
History
State Route 23 has been designated as such since 1934. However, at this time it was also designated as Legislative Route 155. The freeway portion of SR 23 opened in several phases between 1971 and 1994. Before then, SR 23 intersected with U.S. 101 near Newbury ParkNewbury Park, California
The community of Newbury Park, California is located in the western portion of the city of Thousand Oaks and Casa Conejo, an unincorporated area of southeastern Ventura County's Conejo Valley, which is also in the northwestern Greater Los Angeles Area...
, although it still ran concurrently with U.S. 101, which was then an expressway.
SR 23 was designated as part of the Freeway and Expressway System in 1959.
Decker Freeway
Decker Freeway was a never built north–south freeway that would connect CA 118, US 101, and CA 1California State Route 1
State Route 1 , more often called Highway 1, is a state highway that runs along much of the Pacific coast of the U.S. state of California. It is famous for running along some of the most beautiful coastlines in the world, leading to its designation as an All-American Road.Highway 1 does not run...
. The freeway was part of a 1958 plan by the Metropolitan Engineering Board, but was later considered to be geographically improbable and the plans were abandoned.
The freeway's southern portion, from CA 1 to US 101, follows the general alignment of Decker Canyon Road and Westlake Blvd, a segment of CA 23. It would continue north before terminating at CA 118 near First Street.
Major intersections
- Note: Except where prefixed with a letter, postmiles were measured in 1964, based on the alignment as it existed at that time, and do not necessarily reflect current mileage. The numbers reset at county lines; the start and end postmiles in each county are given in the county column.
{| class=wikitable
!County
!Location
!Postmile
!Exit
Exit number
An exit number is a number assigned to a road junction, usually an exit from a freeway. It is usually marked on the same sign as the destinations of the exit, as well as a sign in the gore....
!Destinations
!Notes
|-
|Los Angeles
Los Angeles County, California
Los Angeles County is a county in the U.S. state of California. As of 2010 U.S. Census, the county had a population of 9,818,605, making it the most populous county in the United States. Los Angeles County alone is more populous than 42 individual U.S. states...
LA 0.00-8.90
|Malibu
|0.00
|
|
|
|-
|rowspan=18|Ventura
Ventura County, California
Ventura County is a county in the southern part of the U.S. state of California. It is located on California's Pacific coast. It is often referred to as the Gold Coast, and has a reputation of being one of the safest populated places and one of the most affluent places in the country...
VEN 0.00-24.17
|rowspan=12|Thousand Oaks
Thousand Oaks, California
Thousand Oaks is a city in southeastern Ventura County, California, in the United States. It was named after the many oak trees that grace the area, and the city seal is adorned with an oak....
|T1.49
|
|Portrero Road – Hidden Valley
|
|-
|R2.26
|
|Triunfo Canyon Road
|
|-
|R2.88
|
|Agoura Road, Hampshire Road
|
|-bgcolor=#ddffdd
|R3.32
0.70Indicates that the postmile represents the distance along US 101 rather than SR 23.
|
|
|Interchange; south end of US 101 overlap
|-
|colspan=4 align=center|South end of freeway on US 101
|-
|1.62
|41
|Hampshire Road
|
|-bgcolor=#ddffdd
|3.11
R3.34
|12B
|
|North end of US 101 overlap; no exit number northbound
|-bgcolor=#ffdddd
|R3.70
|13
|Hillcrest Drive, Thousand Oaks Boulevard – Thousand Oaks
Thousand Oaks, California
Thousand Oaks is a city in southeastern Ventura County, California, in the United States. It was named after the many oak trees that grace the area, and the city seal is adorned with an oak....
|Southbound exit and northbound entrance
|-
|R5.06
|14
|Janss Road
|
|-
|R6.03
|15
|Avenida de los Arboles
|
|-
|R7.17
|16
|Sunset Hills Boulevard
|
|-
|R8.21
|17
|Olsen Road – Simi Valley
Simi Valley, California
-2010:The 2010 United States Census reported that Simi Valley had a population of 124,237. The population density was 2,940.8 people per square mile...
|
|-
|rowspan=4|Moorpark
Moorpark, California
Moorpark is a city in Southern California. It was founded in 1900 by Robert Poindexter, presumably named after the moorpark apricots that grew in the area. The city has experienced a great amount of growth since the late 1970s...
|R10.16
|19
|Tierra Rejada Road
|
|-
|colspan=4 align=center|North end of freeway
|-bgcolor=#ddffdd
|R11.43
T18.21Indicates that the postmile represents the distance along SR 118
California State Route 118
State Route 118 is a state highway in the U.S. state of California that begins running west to east through Ventura and Los Angeles counties in southern California. It travels from Saticoy in Ventura County east to Lake View Terrace in Los Angeles...
rather than SR 23.
|20B
|
|Interchange; south end of SR 118 overlap
|-bgcolor=#ddffdd
|R17.49
R12.90
|
|
|North end of SR 118 overlap
|-
|rowspan=2|Fillmore
Fillmore, California
Fillmore is a city in Ventura County, California, United States. The population was 15,002 at the 2010 census, up from 13,643 at the 2000 census.- History :...
|24.17
|
|
|
|-
|24.17
|
|A Street
|Continuation beyond SR 126