Interstate 15 in California
|Defined by Streets and Highways Code § 315|
|Maintained by Caltrans|
|Length:||293.64 mi[a] (472.57 km)|
|Existed:||1957 – present|
|South end:||32nd Street / Norman Scott Road in San Diego|
| I-5 in San Diego
I-805 in San Diego
I-8 in San Diego
I-215 in Murrieta
I-10 in Ontario
SR 210 in Rancho Cucamonga
I-215 in San Bernardino
US 395 in Hesperia
SR 58 in Barstow
I-40 in Barstow
|North end:||I‑15 at Nevada state line|
Route 15, consisting of the contiguous segments of State Route 15 (SR 15) joined by Interstate 15 (I-15), is a major north–south state highway in the U.S. state of California, connecting San Bernardino, Riverside, and San Diego Counties. The route consists of the southernmost 287.26 miles (462.30 km) of I-15, a major Interstate Highway that extends north through Nevada, Arizona, Utah, Idaho, and Montana to the Canada–US border. It is a major thoroughfare for traffic between San Diego and the Inland Empire, as well as between Southern California, Las Vegas, Nevada, and points beyond.
South of its junction at Interstate 8 in San Diego, the highway becomes SR 15, extending 5.59 miles (9.00 km) to Interstate 5, about 12 miles (19 km) from the Mexican border. This segment was initially signed as a state route instead of an Interstate, but it is being upgraded to Interstate standards so it would become part of I-15 in the future. Including this segment, the entire length of Route 15 is 293.64 miles (472.57 km).
Interstate 15 has portions designated as the Escondido Freeway, Avocado Highway, Temecula Valley Freeway, Ontario Freeway, Barstow Freeway, CHP Officer Larry L. Wetterling and San Bernardino County Sheriff's Lieutenant Alfred E. Stewart Memorial Highway, or Mojave Freeway.
SR 15 is part of the California Freeway and Expressway System. SR 15 begins south of I-5 at 32nd Street near Harbor Drive. After this, SR 15 has an interchange with SR 94, which has been cited as not being up to Interstate standards. The route interchanges with I-805; however, one can only continue in the same direction that they were going at this interchange, since this is the interchange of two north–south freeways, resulting in the overall shape of an "X." Between the Polk Avenue and Orange Avenue overpasses, the freeway goes under a city park that was built on top of the freeway during construction in 2001. Pedestrian bridges were also built at Monroe Avenue and Landis Street to reduce the effects of the freeway geographically dividing the community. Between I-8 and I-805, SR 15 follows the former alignment of 40th Street, which was its former routing as a city street. It continues seamlessly into the southern terminus of I-15 at I-8 in San Diego. On the northbound conversion to I-15 at I-8, there is no "End SR 15" sign.
I-15 is part of the California Freeway and Expressway System, and it is eligible for designation as a state highway within the State Scenic Highway System; however the state transportation authority, Caltrans, has not done so. There are various local names for the highway, such as the Escondido Freeway between San Diego and Escondido. I-15 between SR 163 and Pomerado Road/Miramar Road is known as the Semper Fi Highway in recognition of the nearby Marine Corps Air Station Miramar. North of the Escondido city limits it is known as the Avocado Highway, whose designation ends upon entering Temecula. There are other local names as noted below.
Heading northward, I-15 currently begins at I-8, at the same place that its continuation, SR 15, begins its southward journey. I-15 goes through Mission Valley and intersects with SR 52, before merging with SR 163. After traversing the Marine Corps Air Station Miramar, I-15 comes into Rancho Peñasquitos, where it intersects with the end of SR 56. Northward, the route crosses Lake Hodges inside the upper San Diego city limits. I-15 continues north into Escondido, where it interchanges with SR 78.
North of Escondido, I-15 goes through hilly terrain and farmland, descending to the town of Fallbrook and intersecting SR 76 (SR 76), before it crosses the county line into Riverside County and descends to the Inland Empire. In Riverside County, SR 79 joins I-15 and runs concurrently with the route for a 3.2-mile (5 km) portion in Temecula, before it splits away running north to Hemet. Then, I-15 intersects with the southern end of I-215, which continues the designation of the Escondido Freeway. I-15 continues north as the Temecula Valley Freeway.
In Murrieta, I-15 splits from its first and only spur route in California, I-215, which runs through the two largest cities in the Inland Empire, San Bernardino and Riverside. I-15 runs along the eastern edge of the Santa Ana Mountains, passing the city of Lake Elsinore. In the city of Lake Elsinore, I-15 intersects SR 74, an important surface route connecting the Coachella Valley with the communities of Idyllwild, Hemet, Perris, Lake Elsinore and San Juan Capistrano. It continues through the suburban areas in the western Inland Empire, passing Corona and Ontario, California. During this stretch of the highway, I-15 intersects SR 91, a major east-west highway, in Corona; the oft-congested interchange serves as an important link from Southwest Riverside County to Riverside and Orange County. North of the SR 91, I-15 continues through the bedroom communities of Norco and Eastvale, while skirting the western edge of the city of Jurupa Valley. I-15 enters San Bernardino County at its intersection with SR 60, another major east-west highway, which connects I-15 with the city of Ontario and the Chino Valley. I-15 passes through the city of Ontario on its way to another major intersection with I-10, the main east-west artery though Southern California. North of I-10, I-15 passes through the major suburban communities of Rancho Cucamonga and Fontana as the highway intersects SR 210, an east-west highway skirting the San Bernardino Mountain Range. SR 210 connects I-15 to major foothill communities, such as Pasadena, Rialto and San Bernardino. I-15 also crosses old US Route 66 during this stretch of highway, which is signed as SR 66, Foothill Blvd. At this juncture, I-15 takes a strongly northeastern alignment as it moves to rejoin with its spur route, I-215, in Devore, north of the city of San Bernardino. The highway is then rejoined by I-215, before heading northwards and upward through the Cajon Pass, an important mountain pass that is the primary route between Southern California and points eastwards and northeastwards.
The portion of I-15 that is located between its northern and southern junctions with I-215 is also used by many local residents as the major north–south route for the western portions of the San Bernardino-Riverside-Ontario metropolitan area. (I-215 serves a similar function in the eastern portion of the metropolitan area. These two highways are the only continuous north–south freeways in the area.)
North of Limonite Avenue (south of SR 60), I-15 is known as the Ontario Freeway. After its merger with I-215 in Devore, I-15 is called the Barstow Freeway or the Mojave Freeway. A short section between SR 138 and Oak Hill Road is also designated as the CHP Officer Larry L. Wetterling and San Bernardino County Sheriff’s Lieutenant Alfred E. Stewart Memorial Highway, named after two officers killed in the line of duty. On this stretch of highway, I-15 northbound splits from I-15 southbound, where the road ascends up a steep grade until it reaches Cajon Summit (elevation 4190 feet) just south of the High Desert community of Apple Valley. Tractor Trailer trucks headed southbound are advised to travel at 35 mph or less due to the steep downward grade. The southbound lanes provide runaway truck ramps as a safety feature. The two halves of the highway rejoin shortly before reaching Cajon Summit.
North of the Cajon Pass, I-15 traverses the Mojave Desert towns of Hesperia and Victorville. I-15 passes through desert for 30 miles (48 km) before reaching Barstow, then continues past Zzyzx Road, before reaching the town of Baker. The sign for Zzyzx Road — alphabetically the last place name in the world — is a landmark of sorts on the drive between Los Angeles and Las Vegas. I-15 enters Nevada near the casino town of Primm, formerly known as Stateline, Nevada.
I-15 continues thereafter to Las Vegas, Salt Lake City, and on into Idaho and Montana, before ending at the Canada–US border, where Alberta Highway 4 continues the ribbon of asphalt into Canada. Because it joins with the western end of I-70 in Southwestern Utah, I-15 also forms part of a major east–west corridor connecting Southern California with Denver, St. Louis, and points east.
The Mojave Freeway is fairly busy on weekdays, since it connects the rapidly growing exurbs of the Victor Valley with the Los Angeles area. On weekends and holidays, however, it can sometimes be jammed with Californians driving to Las Vegas for short vacations.[b]
Construction is currently underway to rehabilitate the pavement on I-15 and to add truck lanes to separate autos from truck traffic.
|This section needs expansion. You can help by adding to it. (January 2015)|
I-15 was initially planned to run from I-10 in San Bernardino along the current I-215 alignment then up through the Cajon Pass and on to Las Vegas, with a distance of 186.24 miles (299.72 km) within the state. California successfully argued the addition south to San Diego, suggesting that the freeway would connect the major military bases, the former March AFB (now March ARB) and the former NAS Miramar (now MCAS Miramar). US 395 was then signed TEMP-15 and the "old" I-15 between Devore and San Bernardino became I-215.
On January 24, 1957, the State Highway Commission defined the Escondido Freeway as what are now Routes 15 and 215 from Route 805 to Route 91. This entire segment was previously U.S. Route-395 when it was named. Since then, the definition was extended on Route 15 south to Route 8 by Assembly Concurrent Resolution 34, Chapter 67 in 1979. Meanwhile, the segment of Route 15 from the San Diego County Line to the I-15/I-215 interchange was named the Temecula Valley Freeway in 1990.
This legal definition has been amended twice: First in 1990, the California Assembly passed Concurrent Resolution 125, Chapter 78, renaming I-15 between the San Diego County Line (which is further south from Interstate 215) and Bundy Canyon Road near Lake Elsinore as the Temecula Valley Freeway.
Then in 1993, the California Assembly passed legislation officially designating State Route 71 as a part of the Chino Valley Freeway. However, the name "Corona Freeway" is, confusingly, sometimes still applied to this portion of State Route 71; thus, despite the official change, guide signs on I-10 eastbound and SR 57 southbound at the Kellogg Interchange in Pomona still refer to SR 71 as the "Corona Freeway".
Present SR 15 was signed after the creation of I-15 in 1968. Since I-15's terminus was at I-8, SR 15 was signed mostly along 40th Street and Wabash Boulevard in San Diego to its merge with I-5. The portion between Adams Avenue and Interstate 805 remained a city street for a long time, and this portion was not completed until January 2000. For this reason, the freeway is often referred to as the 40th Street Freeway.
Before the completion of the freeway, from 1968 to 1992, the neighborhood was known for prostitution, drugs, drive-by shootings, and gangs. The indirect cause of all this was due to Caltrans' plans to build a freeway in this area on land where houses were. Because families did not want to live in these houses since they would be soon torn down, they rented them to those who were only going to be in the area on a temporary basis; many of these people were involved in illegal activities. Even though the freeway was officially added to the Caltrans proposals as early as 1968, it was not until March 1992 that construction began. Many in the city opposed the building of this freeway, although some petitioned for the freeway to be built because of the poor conditions in the neighborhood.
State Route 31
In 1933, Interstate 15 was defined as Legislative Route 193, running from pre-1964 Legislative Route 43 (present State Route 91) in Corona to pre-1964 Legislative Route 9 (now State Route 66), and was extended north to pre-1964 Legislative Route 31 (present I-15 and I-215) in 1935. The piece south of U.S. Route 60 (Mission Boulevard), running along North Main Street, Hamner Avenue and Milliken Avenue, was state-maintained by 1955, but was not assigned a signed number. This was still the only existing piece in 1963, and had a planned freeway replacement to the east.
In the 1964 renumbering, the route was assigned as State Route 31. It was added to the Interstate Highway System in February 1972 as a realignment of Interstate 15 (the former alignment became Interstate 15E). Legislative changes were made in 1974, eliminating SR 31 (along with State Route 71 south of Corona) in favor of I-15. However, SR 31 continued to be signed — as temporary Interstate 15 - until present I-15 was finished. (A 1986 map shows state maintenance continuing north past SR 60 to Jurupa Street, where it turned east to I-15.)
Most of Interstate 15 is undergoing major improvements from Devore to the Nevada State Line, beginning in 2002 and costing $349 million. This project will improve traffic flow on the heavily traveled highway for those going to and from Las Vegas. Most of the construction was completed by winter 2009. Projects include adding 39 miles (63 km) of truck lanes on hills at various locations, repaving 76 miles (122 km) of I-15 at various locations, adding exit numbers, renovating and rehabilitating the rest area between Baker and the Nevada State Line (Valley Wells Rest Area), reconstructing bridges in Baker, and moving the agriculture inspection station from Yermo to the Nevada State Line and including a truck weigh station.
As of March 2008, construction is underway to add a northbound truck descending lane and to repave lanes between Bailey Road and Yates Well Road.
Redesignation of SR-15 as I-15 will eventually occur when the freeway's interchange with SR-94 is upgraded to Interstate standards. The interchange currently has left-exits and blind merges, and is due to be updated with a long-awaited widening of both SR-15 and SR-94 by 2019. At that time SR-15 will be resigned as part of I-15. The remaining portion of SR-15 conforms with Interstate standards.
|San Diego||San Diego||32nd Street, Norman Scott Road to Harbor Drive||South end of SR 15/Escondido Freeway|
|0.00||0.00||1A||Main Street||Southbound exit and northbound entrance; south end of state maintenance|
|1B-C||I-5 (Montgomery Freeway) – National City, Chula Vista||Southbound exit and northbound entrance; left exit to I-5 south; signed as exits 1B (north) and 1C (south); I-5 exit 13A|
|0.60||0.97||1D||Ocean View Boulevard, Imperial Avenue||Signed as exit 1 northbound|
|2.23||3.59||2B-C||SR 94 (M. L. King Jr. Freeway) / Home Avenue||Signed as exits 2B (east) and 2C (west) northbound; southbound exit to SR 94 east is via exit 3; SR 94 east exits 2A and 2C, west exit 2|
|3.37||5.42||3||I-805 north (Jacob Dekema Freeway) – Los Angeles||Northbound exit and southbound entrance; I-805 south exit 14|
|I-805 south (Jacob Dekema Freeway) to SR 94 east||Southbound exit and northbound entrance; I-805 north exit 14|
|4.66||7.50||5A||University Avenue – City Heights Transit Plaza|
|5.07||8.16||5B||El Cajon Boulevard – Boulevard Transit Plaza||Former I-8 Bus.|
|6.13||9.87||6B||I-8 / Camino del Rio South – Beaches, El Centro||North end of SR 15; south end of I-15; I-8 exits 7A-B|
|6.82||10.98||7||Friars Road – Qualcomm Stadium||Signed as exits 7A (east) and 7B (west) northbound|
|9.24||14.87||9||Balboa Avenue, Tierrasanta Boulevard||Former SR 274 west|
|10.00||16.09||10||Clairemont Mesa Boulevard||Southbound exit is part of exit 11|
|10.58||17.03||11||SR 52||SR 52 exit 7|
|I-15 Express Lanes||South end of Express Lanes|
|—||SR 163 south||Southbound exit and northbound entrance for Express Lanes only|
|12.12||19.51||12||SR 163 south (Cabrillo Freeway)||Southbound exit and northbound entrance; former US 395 south|
|13.33||21.45||13||Miramar Way||Serves Marine Corps Air Station Miramar|
|14.29||23.00||14||Miramar Road, Pomerado Road|
|15.00||24.14||15||Carroll Canyon Road|
|—||Hillery Drive – Mira Mesa||Express Lanes access only|
|15.92||25.62||16||Mira Mesa Boulevard|
|17.31||27.86||17||Mercy Road, Scripps Poway Parkway|
|18.18||29.26||18||Poway Road (CR S4), Rancho Peñasquitos Boulevard|
|—||SR 56 west / Ted Williams Parkway||Northbound exit and southbound entrance for Express Lanes only|
|—||Sabre Springs-Peñasquitos Transit Station||Express Lanes access only|
|19.47||31.33||19||SR 56 west (Ted Williams Freeway) / Ted Williams Parkway||SR 56 exit 9|
|20.57||33.10||21||Carmel Mountain Road|
|21.92||35.28||22||Camino del Norte|
|22.94||36.92||23||Bernardo Center Drive|
|—||George Cooke Express Drive – Rancho Bernardo||Express Lanes access only|
|23.69||38.13||24||Rancho Bernardo Road|
|26.03||41.89||26||Pomerado Road (CR S5), West Bernardo Drive|
|Escondido||26.97||43.40||27||Via Rancho Parkway|
|—||Del Lago Boulevard, Beethoven Drive||Express Lanes access only|
|28||Centre City Parkway (I-15 Bus. north)||Northbound exit and southbound entrance; former US 395 north|
|28.77||46.30||29||Felicita Road, Citricado Parkway|
|30.09||48.43||30||9th Avenue, Auto Park Way|
|30.63||49.29||31||Valley Parkway – Downtown Escondido|
|—||Hale Avenue||Northbound exit and southbound entrance for Express Lanes only|
|I-15 Express Lanes||North end of Express Lanes|
|31.52||50.73||32||SR 78 – Oceanside, Ramona||SR 78 west exit 17, east exits 17A-B.|
|32.86||52.88||33||El Norte Parkway|
|33.92||54.59||34||Centre City Parkway (I-15 Bus. south)||Southbound exit and northbound entrance; former US 395 south|
|||36.64||58.97||37||Deer Springs Road (CR S12), Mountain Meadow Road|
|||40.84||65.73||41||Gopher Canyon Road, Old Castle Road|
|||43.28||69.65||43||Old Highway 395||Former US 395|
|||46.49||74.82||46||SR 76 – Pala, Oceanside|
|||50.59||81.42||51||Mission Road (CR S13) – Fallbrook|
|||54.07||87.02||54||Rainbow Valley Boulevard|
|Riverside||Temecula||57.70||92.86||58||SR 79 south (Temecula Parkway) – Temecula, Indio||South end of SR 79 overlap; former SR 71 south|
|59.24||95.34||59||Rancho California Road, Old Town Front Street|
|60.88||97.98||61||SR 79 north (Winchester Road)||North end of SR 79 overlap|
|62||French Valley Parkway||Southbound exit only|
|Murrieta||63.00||101.39||63||I-215 north (Escondido Freeway north) – Riverside, San Bernardino||Northbound exit and southbound entrance; former I-15E north / US 395 north|
|63.73||102.56||64||To I-215 north / Murrieta Hot Springs Road – Riverside|
|64.85||104.37||65||California Oaks Road, Kalmia Street|
|Wildomar||67.90||109.27||68||Clinton Keith Road|
|70.56||113.56||71||Bundy Canyon Road|
|Lake Elsinore||73.42||118.16||73||Diamond Drive, Railroad Canyon Road|
|75.21||121.04||75||Main Street (I-15 Bus. north)|
|76.54||123.18||77||SR 74 (Central Avenue) – San Juan Capistrano, Perris|
|80.95||130.28||81||Lake Street (I-15 Bus. south)|
|||84.66||136.25||85||Indian Truck Trail|
|||87.65||141.06||88||Temescal Canyon Road||Former SR 71|
|Corona||89.90||144.68||90||Weirick Road, Dos Lagos Drive|
|92.08||148.19||92||El Cerrito Road|
|92.95||149.59||93||Ontario Avenue||Former SR 71|
|95.76||154.11||96||SR 91 (Riverside Freeway) – Riverside, Beach Cities||Signed as exits 96A (east) and 96B (west) southbound; former US 91; SR 91 exit 51|
|Norco||97.14||156.33||97||Hidden Valley Parkway|
|97.90||157.55||98||Second Street (I-15 Bus. north)|
|99.86||160.71||100||Sixth Street (I-15 Bus. south)|
|Eastvale||102||Schleisman Road||Proposed interchange|
|Jurupa Valley||105||Cantu-Galleano Ranch Road|
|105.73||170.16||106||SR 60 (Pomona Freeway) – Los Angeles, Riverside||Signed as exits 106A (east) and 106B (west) northbound; SR 60 east exit 41, west exit 41A|
|San Bernardino||Ontario||107.55||173.08||108||Jurupa Street||Former SR 31 south|
|108.93||175.31||109||I-10 (San Bernardino Freeway) – Los Angeles, San Bernardino, Indio||Signed as exits 109A (west) and 109B (east) southbound; former US 99; I-10 west exit 58, east exits 58A-B|
|Ontario–Rancho Cucamonga line||109.59||176.37||110||4th Street|
|Rancho Cucamonga||111.85||180.01||112||SR 66 (Foothill Boulevard)||Former US 66|
|115||SR 210 (Foothill Freeway) – Pasadena, San Bernardino, Redlands||Signed as exits 115A (east) and 115B (west) northbound and exits 115A (west) and 115B (east) southbound; SR 210 exit 64A|
|117.91||189.76||118||Duncan Canyon Road||Opened on October 23, 2015 for traffic and pedestrian use|
|San Bernardino||122.19||196.65||122||Glen Helen Parkway|
|122.91||197.80||123||I-215 south (Barstow Freeway south) – San Bernardino, Riverside||Left exit southbound; former I-15E south / US 66 west / US 91 south / US 395 south; I-215 exit 54B|
|124.09||199.70||124||Kenwood Avenue||Former US 66 east|
|||129.14||207.83||129||Cleghorn Road||Former US 66 west|
|||130.50||210.02||131||SR 138 – Palmdale, Silverwood Lake|
|||137.75||221.69||138||Oak Hill Road|
|Hesperia||141.45||227.64||141||US 395 north – Bishop, Adelanto||Northbound exit and southbound entrance|
|To US 395 north / Joshua Street||Southbound exit and northbound entrance|
|143.13||230.35||143||Main Street – Hesperia, Phelan|
|Victorville||146.72||236.12||147||Bear Valley Road – Lucerne Valley|
|148||La Mesa Road, Nisqualli Road|
|149.64||240.82||150||SR 18 west (Palmdale Road) / I-15 Bus. north (7th Street)||South end of SR 18 overlap; former US 66 east / US 91 north|
|150.56||242.30||151A||Roy Rogers Drive|
|152.62||245.62||153A||SR 18 east / I-15 Bus. south (D Street) – Victorville, Apple Valley||North end of SR 18 overlap; former US 66 / US 91|
|153.53||247.08||154||Stoddard Wells Road|
|||156.64||252.09||157||Stoddard Wells Road – Bell Mountain|
|||160.96||259.04||161||Dale Evans Parkway – Apple Valley|
|||164.82||265.25||165||Wild Wash Road|
|Barstow||174.97||281.59||175||Outlet Center Drive|
|179.46||288.81||179||SR 58 west – Bakersfield|
|180.78||290.94||181||I-15 Bus. east (L Street) / W. Main Street|
|182.67||293.98||183||SR 247 south (Barstow Road)|
|183.55||295.40||184A||I-40 east (Needles Freeway) – Needles||Northbound exit and southbound entrance; southbound access is via exit 184|
|184.08||296.25||184B||I-15 Bus. / CR 66 (E. Main Street)||Signed as exit 184 southbound; former US 66|
|186.01||299.35||186||Old Highway 58 west||Former US 91 south/US 466/SR 58 west|
|||188.72||303.72||189||Fort Irwin Road||Serves Fort Irwin|
|||190.96||307.32||191||Ghost Town Road||Serves the ghost town of Calico|
|Yermo||193.77||311.84||194||Calico Road – Yermo|
|195.51||314.64||196||Yermo Road – Yermo|
|Agricultural Inspection Station (southbound only)|
|||216.53||348.47||Clyde V. Kane Rest Area|
|Zzyzx||239.31||385.13||239||Zzyzx Road – Zzyzx|
|Baker||244.95||394.21||245||Baker Boulevard (I-15 Bus. north) – Baker||Northbound exit and southbound entrance; former US 91 north / US 466 east|
|245.70||395.42||246||SR 127 north / Kelbaker Road – Death Valley|
|247.59||398.46||248||Baker Boulevard (I-15 Bus. south) – Baker||Southbound exit and northbound entrance; former US 91 south / US 466 west|
|Halloran Springs||258.74||416.40||259||Halloran Springs Road|
|||264.70||425.99||265||Halloran Summit Road|
|||270.29||434.99||Valley Wells Rest Area|
|||Joint Port of Entry (southbound only)||Under construction. Will replace the Yermo Agricultural Inspection Station.|
|||290.53||467.56||291||Yates Well Road|
|||295.37||475.35||I‑15 north – Las Vegas||Continuation into Nevada|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi
- Mileage is the entire route, including both SR 15 and I-15
- The highway was featured on the television program Dangerous Drives (Speed), which illustrated the difficulties of patrolling the highway due to excessive speed and congestion. The 45-minute episode "Dangerous Drives: Highway Patrol" originally aired in January 2010.
- "California Log of Bridges on State Highways". California Department of Transportation. January 1, 2006. Retrieved November 28, 2011.
- Staff (October 31, 2002). "Table 1: Main Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways as of October 31, 2002". Route Long and Finder List. Federal Highway Administration. Retrieved November 29, 2011.
- California State Legislature. "Section 250-257". Streets and Highways Code. Legislative Counsel of California. Retrieved November 28, 2011.
- California Road Atlas and Driver's Guide (Map). Thomas Brothers. 2000. p. 214, 216.
- "California Highways: Routes 9 through 16". Retrieved May 1, 2008.[self-published source]
- Caltrans District 11 Fact Sheet for SR 15 Project Archived June 9, 2008, at the Wayback Machine.
- "California 15 and Interstate 15 north from Interstate 5 to California 163". California @ AARoads.com. Retrieved May 1, 2008.[self-published source]
- California Assembly. "Section 260–284". Streets and Highways Code. Legislative Counsel of California. Retrieved November 29, 2011.
- Cadd, Dennis (July 11, 2012). "Officially Designated Scenic Highways". California Department of Transportation. Retrieved July 18, 2012.
- Faigin, Daniel P. (July 18, 2012). "Routes 9 through 16". California Highways. Self-published. Retrieved July 18, 2012.[self-published source]
- California Road Atlas and Driver's Guide (Map). Thomas Brothers. 2000. p. V, 99, 106.
- "ACR-127 CHP Officer Larry L. Wetterling and San Bernardino County Sheriff's Lieutenant Alfred E. Stewart Memorial Highway". California Legislative Information. Retrieved May 22, 2013.
- "Interstate 15 Express Lanes". Sandag.org. Retrieved March 31, 2012.
- Caltrans 2009, p. 60
- Caltrans 2009, p. 63
- Caltrans 2009, p. 69
- Caltrans 2009, p. 67
- Brooks, Jeanne F. (January 9, 2000). "A Neighborhood's Rough Road: Mid City's I-15 Stretch to Open After Tortuous 40-Year saga". The San Diego Union-Tribune. Copley News Service. Retrieved January 18, 2008 – via ProQuest. (subscription required (. ))[dead link]
- Faigin, Daniel P. (July 18, 2012). "Routes 193 through 200". California Highways. Self-published. Retrieved July 18, 2012.[self-published source]
- 1955 Gousha Los Angeles district map (Map). H.M. Gousha. Archived from the original on July 26, 2011. Retrieved November 29, 2011.
- 1963 Caltrans Los Angeles and vicinity map (Map). Retrieved November 29, 2011.
- Faigin, Daniel P. (July 18, 2012). "Interstate Highway Types and the History of California's Interstates". California Highways. Self-published. Retrieved July 18, 2012.[unreliable source?]
- Faigin, Daniel P. (July 18, 2012). "Routes 25 through 32". California Highways. Retrieved July 18, 2012.[self-published source]
- 1986 Caltrans Los Angeles and vicinity map (Map). Retrieved November 29, 2011.
- Interstate 15 Major Improvements from Barstow to Nevada stateline (PDF) (Map). California Department of Transportation. June 2004. Archived from the original (PDF) on September 11, 2008.
- Warring, KS (January 14, 2007). "Interstate 15 Freeway Interchanges" (PDF). California Numbered Exit Uniform System. California Department of Transportation. Retrieved February 5, 2009.
- Bender, Mary (July 20, 2005). "Country Road to Get New Course: Schleisman, Plans Are Under Way to Widen the Artery in the High-Growth Area, and Link it to I-15". City of Riverside. Retrieved July 18, 2012.
- "Environmental Assessment for Interstate 15 Joint Port of Entry" (PDF). Bureau of Land Management-Needles Field Office. Retrieved 2014-06-24.
- Caltrans (January 2009). 2008 Named Freeways, Highways, Structures and Other Appurtenances in California (PDF). California Department of Transportation. Retrieved November 29, 2011.
|Wikimedia Commons has media related to Interstate 15 in California.|
- Interstate 15 Express Lanes in San Diego County
- Interstate 15 @ Interstate-Guide.com
- California @ AARoads.com – Interstate 15
- Caltrans: Interstate 15 highway conditions
- California Highways: Interstate 15