{{Short description|North–south Interstate and state highway in California, United States}} {{highway detail hatnote|Interstate 15}} {{For|the original Route 15 in California|California State Route 15 (1934-1964)}} {{Use mdy dates|date=August 2014}} {{Infobox road | state = CA | type = ISR | route = 15 | section = 315 | allocation = *{{jct|state=CA|SR|15|nolink1=yes}} from 32nd Street in San Diego to I-8 *{{jct|state=CA|I|15|nolink1=yes}} from I-8 to Nevada state line | map = {{maplink-road|from=Interstate 15 in California.map}} | map_custom = yes | map_notes = I-15 highlighted in red, SR&nbsp;15 in purple | length_mi = 295.37 | length_ref = <ref name="bridge log">{{Caltrans bridgelog|date=July 2007}}</ref><ref name= "mileage" group=lower-alpha>Mileage is the entire route, including both SR 15 and I-15</ref> | established = 1957 | direction_a = South | terminus_a = {{Jct|state=CA|I|5}} in San Diego | junction = <!-- PER WP:USRD/STDS NO MORE THAN 7-10 MAJOR INTERSECTIONS HERE!!! DO NOT ADD ANYMORE JUNCTIONS!--> *{{jct|state=CA|I|805}} in San Diego *{{Jct|state=CA|I|8}} in San Diego *{{Jct|state=CA|I|215}} in Murrieta *{{Jct|state=CA|SR|91}} in Corona *{{Jct|state=CA|SR|60}} in Jurupa Valley *{{Jct|state=CA|I|10}} in Ontario *{{Jct|state=CA|SR|210}} in Rancho Cucamonga *{{Jct|state=CA|I|215}} in San Bernardino *{{Jct|state=CA|US|395}} in Hesperia *{{Jct|state=CA|I|40}} in Barstow | direction_b = North | terminus_b = {{Jct|state=NV|I|15}} at the Nevada state line in Primm, NV | counties = San Diego, Riverside, San Bernardino | previous_type = SR | previous_route = 14 | next_type = SR | next_route = 16 }} '''Route&nbsp;15''', consisting of the contiguous segments of '''State Route&nbsp;15''' ('''SR&nbsp;15''') and '''Interstate&nbsp;15''' ('''I-15'''), is a major north–south state highway and Interstate Highway in the U.S. state of California, connecting San Diego, Riverside, and San Bernardino counties. The route consists of the southernmost {{convert|289.24|mi|km}}<ref name="FHWA">{{cite web |author = Federal Highway Administration |url = https://www.fhwa.dot.gov/planning/national_highway_system/interstate_highway_system/routefinder/?redirect |title = Table 1: Main Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways as of October 31, 2002 |work = Route Long and Finder List |publisher = Federal Highway Administration |date = October 31, 2002 |access-date = November 29, 2011 |author-link = Federal Highway Administration }}</ref> of I-15, which 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 the Intermountain West.

South of its junction at I-8 in San Diego, the highway becomes SR&nbsp;15, extending {{convert|6.13|mi|km}}<ref name="bridge log"/> to I-5, about {{convert|12|mi|km}} from the Mexico–United States 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&nbsp;15 is {{convert|295.37|mi|km}}<ref name="bridge log"/> in California.

I-15 has portions designated as the Escondido Freeway, Avocado Highway, Temecula Valley Freeway, Corona 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. It is also known colloquially as "'''the 15'''" to residents of Southern California.

==Route description== {{More citations needed section|date=June 2023}} {{Multiple image | direction = vertical | width = 250 | image1 = CAstateRoute15overpass.jpg | caption1 = Looking south from the University Avenue overpass in San Diego | image2 = Interstate 15 southbound entering Temecula Valley.jpg | caption2 = I-15 southbound entering the Temecula Valley in Murrieta | image3 = Intersection I-10 and I-15 CA USA.jpg | caption3 = I-10/I-15 interchange in Ontario | image4 = Cave Mountain Interstate 15.jpg | caption4 = West of Baker, the freeway jogs north to pass Cave Mountain | image5 = CroneseCat.JPG | caption5 = Cat Dune sand ramp, Cronese Mountains, southwest of Baker | image6 = Zzyzx road.jpg | caption6 = Exit to Zzyzx | image7 = Interstate15 Shadow Valley.jpg | caption7 = Southbound coming down into Shadow Valley. Halloran Summit is on the skyline, about {{convert|8|mi|km}} away. | image8 = Interstate15 Ivanpah Valley.jpg | caption8 = Northbound Interstate 15 descends from Mountain Pass Into the Ivanpah Valley. Primm on the state line between California and Nevada is seen {{convert|4|mi|km}} down the freeway. }}

Route 15 is defined as follows in section 315 of the California Streets and Highways Code:<ref name="CSHC315">{{Cite web|url=https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=SHC&sectionNum=315.|title=Section 315|work=California Streets and Highways Code|publisher=California Office of Legislative Counsel|location=Sacramento|access-date=August 17, 2025}}</ref>

<blockquote>Route 15 is from:<br /> (a) Route 5 in San Diego to Route 8.<br />(b) Route 8 to the Nevada state line near Stateline, Nevada via the vicinity of Temecula, Corona, Ontario, Victorville, and Barstow.</blockquote>

The section of Route 15 defined in subdivision (a) is not considered an Interstate Highway according to the Federal Highway Administration (FHWA)'s route logs.<ref name="FHWA"/>

I-15 and SR&nbsp;15 are part of the California Freeway and Expressway System,<ref name="cafes">{{CAFESystem}}</ref> and are part of the National Highway System,<ref name=fhwa-nhs>{{FHWA NHS map|region=sandiego|access-date=October 19, 2017}}<br />{{FHWA NHS map|region=californianorth|access-date=October 19, 2017}}</ref> a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration.<ref name=NHS-FHWA>{{FHWA NHS}}</ref> I-15 from SR&nbsp;76 to SR&nbsp;91 and SR&nbsp;58 to SR&nbsp;127 is eligible to be included in the State Scenic Highway System,<ref name="scenic">{{CA scenic}}</ref> but it is not officially designated as a scenic highway by the California Department of Transportation.<ref name="caltransscenic">{{Caltrans scenic|access-date=October 19, 2017}}</ref>

=== San Diego County === SR&nbsp;15 begins south of I-5 at 32nd&nbsp;Street near Harbor Drive. After this, SR&nbsp;15 has an interchange with SR&nbsp;94,<ref name="tgca" /> which has been cited as not being up to Interstate standards.<ref name="cahighways.org">{{cite web |first = Daniel P. |last = Faigin |url = http://cahighways.org/009-016.html#015 |work = California Highways |title = Routes 9 through 16 |access-date = May 1, 2008 }}{{sps|certain=yes|date= August 2014}}</ref> The route then meets I-805; however, one can only continue in the same direction that they were going at this interchange, since the overall shape of this interchange is an elongated "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.<ref>{{cite web |url = http://www.dot.ca.gov/dist11/facts/15-40th.htm |publisher = California Department of Transportation |author = District 11 |title = Fact Sheet for SR&nbsp;15 Project |archive-url = https://web.archive.org/web/20080609064254/http://www.dot.ca.gov/dist11/facts/15-40th.htm |archive-date = June 9, 2008 }}</ref> Between I-805 and I-8, SR&nbsp;15 follows the former alignment of 40th&nbsp;Street, which was its former routing as a city street.<ref name="tgca">{{Cite map |author = Thomas Brothers |title = California Road Atlas and Driver's Guide |year = 2000 |publisher = Thomas Brothers |pages = 214, 216 }}</ref> It continues seamlessly into the southern terminus of I-15 at I-8; on the northbound conversion to I-15 at I-8, there is no "End SR&nbsp;15" sign.{{Cn|date=June 2023}}

There are various local names for the highway, such as the '''Escondido Freeway''' between San Diego and Escondido. I-15 between SR&nbsp;163 and Pomerado Road&nbsp;/ Miramar Road is known as the '''Semper Fi Highway''' in recognition of the nearby Marine Corps Air Station Miramar.<ref name="cahighways.org"/> I-15 between Scripps Poway Parkway and Camino Del Norte is known as the{{anchor|Tony Gwynn Memorial Freeway}} '''Tony Gwynn Memorial Freeway''' in recognition of Tony Gwynn, who played baseball for the San Diego Padres and San Diego State. 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&nbsp;15, begins its southward journey. I-15 goes through Mission Valley and Kearny Mesa, intersecting with SR&nbsp;52 just before merging with SR&nbsp;163. After traversing the Marine Corps Air Station Miramar, I-15 comes into Rancho Peñasquitos, where it meets the eastern end of SR&nbsp;56. Northward, the route crosses Lake Hodges inside the upper San Diego city limits. I-15 continues north into Escondido, where it intersects with SR&nbsp;78.

North of Escondido, I-15 goes through hilly terrain and farmland, passes under the Lilac Road Bridge and approaches the community of Fallbrook near the SR&nbsp;76 interchange. It passes the community of Rainbow, crosses the Riverside county line and descends into the Inland Empire.

=== Inland Empire === In Temecula, I-15 runs concurrently with SR&nbsp;79 for 3.2 miles (5&nbsp;km) before the latter branches off toward Hemet. In Murrieta, I-15 splits from its only auxiliary route in California, I-215, which retains the Escondido Freeway designation and runs through the two largest cities in the Inland Empire, Riverside and San Bernardino. I-15 continues northwest as the '''Temecula Valley Freeway'''.<ref name="tgca2">{{Cite map |author = Thomas Brothers |title = California Road Atlas and Driver's Guide |year = 2000 |publisher = Thomas Brothers |pages = V, 99, 106 }}</ref>

I-15 runs along the eastern edge of the Santa Ana Mountains, passing through the cities of Wildomar and Lake Elsinore. In Lake Elsinore, I-15 intersects SR&nbsp;74, a major highway connecting the city with San Juan Capistrano as well as points east such as Perris, Hemet, Idyllwild, and the Coachella Valley. It continues northwest through the unincorporated area of Temescal Valley as the '''Corona Freeway''' and passes through the city of Corona. During this stretch, I-15 has an interchange with SR&nbsp;91, a major east–west highway; this interchange serves as a vital link between southwestern Riverside County and Orange County. North of SR&nbsp;91, I-15 continues through the city of Norco, crosses the Santa Ana River, and heads due north along the boundary between the cities of Eastvale and Jurupa Valley. I-15 enters San Bernardino County just past an interchange with SR&nbsp;60, another major east–west highway, which connects I-15 with the Chino Valley and the southern San Gabriel Valley. I-15 passes through the city of Ontario on its way to I-10, the main east–west artery though Southern California. North of I-10, I-15 passes through the cities of Rancho Cucamonga and Fontana as it intersects SR&nbsp;210, an east–west highway skirting the San Gabriel and San Bernardino mountain ranges. SR&nbsp;210 connects I-15 to major foothill communities such as Pasadena, Rialto, and San Bernardino. I-15 also crosses old US&nbsp;66 during this stretch of highway, which is signed as SR&nbsp;66, Foothill Boulevard. At this junction, I-15 takes a strongly northeastern alignment as it moves to rejoin with its spur route, I-215, in Devore, in northern San Bernardino. The highway then heads northward and upward through the Cajon Pass, an important mountain pass that is the primary route between Southern California and points further north and east.

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 also the only continuous north–south freeways in the area.)

North of Limonite Avenue (south of SR&nbsp;60), I-15 is known as the '''Ontario Freeway''' (formerly known as the '''Devore Freeway''' prior to 1989). After its northern merge with I-215 in Devore, I-15 is called the '''Barstow Freeway''' or the '''Mojave Freeway'''. A short section between SR&nbsp;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.<ref>{{cite web |title = ACR-127 CHP Officer Larry L. Wetterling and San Bernardino County Sheriff's Lieutenant Alfred E. Stewart Memorial Highway |url = http://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=200920100ACR127 |work = California Legislative Information |access-date = May 22, 2013 }}</ref> 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 {{Convert|4260|ft|m}}) just south of the High Desert communities of Hesperia and Oak Hills. Tractor-trailer trucks headed southbound are required to travel at the posted speed limit of {{Convert|45|mph|km/h|abbr=on}} or less due to the steep downward grade. The southbound lanes provide a runaway truck ramp 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 High Desert cities of Hesperia, where it meets the southern end of US&nbsp;395, and Victorville. I-15 passes through desert for {{convert|25|mi|km}} before reaching Barstow, where it meets the eastern terminus of SR 58 and the western terminus of I-40. It then passes Zzyzx Road more than {{convert|50|mi|km}} later, 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. Northeast of Baker, I-15 passes through the Halloran Summit near Halloran Springs at an elevation of over {{Convert|4000|ft|m}}, then descends into the Shadow Valley before ascending again through the Mountain Pass at an elevation of {{Convert|4730|ft|m}}. A runaway truck ramp is provided for northbound I-15 traffic near the dry Ivanpah Lake at the end of Mountain Pass.{{Cn|date=June 2023}} I-15 then crosses the Nevada state line at the casino town of Primm, Nevada, {{convert|40|mi|km}} southwest of Las Vegas.

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.

===Express lanes=== [[File:I-15 Express Lanes.jpg|left|thumb|250px|The southbound I-15 Express Lanes near Escondido. Note the variable fees for the minimum toll, and for the rates to travel to either SR&nbsp;56 or SR&nbsp;163.]]

There are two sections of high-occupancy toll (HOT) lanes along I-15. The first section is in San Diego County between SR&nbsp;163 in San Diego and SR&nbsp;78 in Escondido. The lanes were originally constructed as reversible carpool lanes in 1988 before they were converted into express lanes a decade later. Between 2004 and 2008, construction extended the lanes north from SR&nbsp;56 to Del Lago Boulevard in Escondido. Then, between 2009 and 2012, work was done to widen the southern reversible segment from two lanes to four, and then extend the corridor north to SR&nbsp;78. The lanes, dubbed a "highway within a highway", include a movable "zipper" barrier for {{convert|16|mi|km}}, which can be changed to create an extra lane as demand allows. In addition, five direct access ramps allow for easier local access, as well as access to bus service from MTS Rapid. These express lanes carry the hidden state highway designation of '''Route 15S''' (for "supplemental").<ref name="SR15S">{{cite web|url=https://postmile.dot.ca.gov/PMQT/PostmileQueryTool.html?type=C&mode=L&lat=33.117690&long=-117.100193&lat2=32.860671&long2=-117.112293|title=Route 15S: Postmile SD 11.89 to SD 30.856|website=Postmile Services Postmile Query Tool|publisher=Caltrans|accessdate=March 26, 2025}}</ref>

The second segment of HOT lanes is in Riverside County, featuring one to two tolled express lanes in each direction from Cajalco Road in Corona to Cantu-Galleano Ranch Road near SR&nbsp;60 at the Eastvale–Jurupa Valley line. These lanes began construction in 2018 and opened in 2021.<ref>{{cite news |title=Completed I-15 Toll Lanes Open Saturday Between Corona, Eastvale |url=https://mynewsla.com/business/2021/04/10/completed-i-15-toll-lanes-open-saturday-between-corona-eastvale-2/ |access-date=April 10, 2021 |publisher=CalNews Inc. |date=April 10, 2021}}</ref>

{{As of|2026|January}}, some toll policies differ between the counties. The HOT lanes in San Diego County are simply branded as the "I-15 Express Lanes" and are administered by the San Diego Association of Governments (SANDAG).<ref name="SANDAG Express"/> The ones in Riverside County are branded as "Riverside Express" and are administered by the Riverside County Transportation Commission (RCTC).<ref name="Riverside Express"/> In both segments, solo drivers are tolled using a congestion pricing system based on the real-time levels of traffic. All tolls are collected using an open road tolling system, and therefore there are no toll booths to receive cash.<ref name="SANDAG Express"/><ref name="Riverside Express"/>

For the segment in Riverside County, carpools with three or more people and motorcycles are not charged. Each vehicle is required to carry a FasTrak ''Flex'' transponder with its switch set to indicate the number of the vehicle's occupants (1, 2, or 3+). Solo drivers and carpools with two people may also use the FasTrak standard tag without the switch. Drivers without any FasTrak tag will be assessed a toll violation regardless of whether they qualified for free.<ref name="Riverside Express">{{cite web | url=https://www.riversideexpress.com/information | title=Information | website=Riverside Express | access-date=January 1, 2026}}</ref>

For the segment in San Diego County, each solo driver is required to carry a FasTrak transponder, while carpools and motorcycles are not charged. SANDAG does not use or offer the switchable FasTrak Flex tags directly, and instead instructs those drivers who do qualify for free to just remove their FasTrak tag off their windshield or cover it in the provided mylar bag to avoid being charged.<ref name="SANDAG Express">{{cite web |url = https://511sd.com/fastrak511sd/how-to-use-the-I-15-Express-Lanes |title = Accessing the I-15 Express Lanes |publisher = San Diego Association of Governments |access-date = January 1, 2026 }}</ref><ref>{{cite AV media | title=Team 10 investigates confusion over Fastrak toll road billing | url=https://www.youtube.com/watch?v=pvOTJ0aNiyI | publisher=KGTV | via=YouTube | date=July 7, 2022}}</ref>

There are long-range plans to extend the Riverside County segment at least as far south as SR&nbsp;74 (Central Avenue) in Lake Elsinore.<ref>{{Cite web|url=https://www.pressenterprise.com/2018/11/09/after-voters-keep-gas-tax-plans-for-15-freeway-toll-lanes-from-corona-to-lake-elsinore-move-ahead/|title=After voters keep gas tax, plans for 15 Freeway toll lanes from Corona to Lake Elsinore move ahead|date=2018-11-09|website=Press Enterprise|language=en-US|access-date=February 23, 2019}}</ref><ref>{{Cite web|url=https://www.rctc.org/funding-received-for-environmental-studies-for-i-15-express-lanes/|title=Funding Received for Extension of I-15 Express Lanes, Cajalco Road to State Route 74|date=2018-03-23|website=Riverside County Transportation Commission|language=en-US|access-date=February 24, 2019}}</ref> A separate project would extend the express lanes from Cantu-Galleano Ranch Road into San Bernardino County as far north as Duncan Canyon Road in Fontana.<ref>{{Cite web | url=https://www.dailybulletin.com/2018/02/28/toll-lanes-could-be-coming-to-15-freeway-through-part-of-san-bernardino-county/ | title=Toll lanes could be coming to 15 Freeway through part of San Bernardino County| date=March 2018}}</ref> Phase 1 of the San Bernardino County extension started construction in March 2025 up to just north of Foothill Boulevard.<ref name="SB Express Lanes Phase 1">{{cite web|url=https://www.gosbcta.com/project/i-15-corridor/|title=I-15 Corridor Freight and Express Lanes Project|accessdate=April 26, 2025}}</ref>

==History== left|thumb|250px|Former southbound agricultural inspection station near Yermo thumb|left|250px|Mojave Freeway in San Bernardino County, California I-15 replaced US&nbsp;395 between San Diego and Temecula, US&nbsp;66 between San Bernardino and Barstow, and US&nbsp;91 north of Barstow.

I-15 was initially planned to run from I-10 near San Bernardino along the current I-215 alignment then up through the Cajon Pass and on to Las Vegas, with a distance of {{convert|186.24|mi|km}} within the state. California successfully argued in favor of 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&nbsp;395 was then signed TEMP-15 and the "old" I-15 between Devore and San Bernardino became part of modern-day I-215.

On January&nbsp;24, 1957, the State Highway Commission defined the Escondido Freeway as what are now Routes&nbsp;15 and 215 from Route&nbsp;805 to Route&nbsp;91. This entire segment was previously US&nbsp;395 when it was named. Since then, the definition was extended on Route&nbsp;15 south to Route&nbsp;8 by Assembly Concurrent Resolution&nbsp;34, Chapter&nbsp;67 in 1979.<ref>{{cite book |author = California Department of Transportation |date = January 2009 |url = http://www.dot.ca.gov/hq/tsip/hseb/products/Named_Freeways.pdf |title = 2008 Named Freeways, Highways, Structures and Other Appurtenances in California |publisher = California Department of Transportation |access-date = November 29, 2011 |url-status = dead |archive-url = https://web.archive.org/web/20121014034335/http://www.dot.ca.gov/hq/tsip/hseb/products/Named_Freeways.pdf |archive-date = October 14, 2012 |page = 60 }}</ref> Meanwhile, the segment of Route&nbsp;15 from the San Diego County Line to the I-15/I-215 interchange was named the Temecula Valley Freeway in 1990.<ref name=caltrans63>{{harvnb| California Department of Transportation |2009|p=63}}</ref>

The original definition for the '''Corona Freeway''', as named by the State Highway Commission on July&nbsp;23, 1958, stated that it was "Routes&nbsp;71, 91, and 15 from Route&nbsp;10 West of Pomona to Route&nbsp;215".<ref>{{harvnb| California Department of Transportation |2009|p=69}}</ref>

This legal definition has been amended twice: First, in 1990, the California Assembly passed Concurrent Resolution&nbsp;125, Chapter&nbsp;78, renaming I-15 between the San Diego County Line (which is further south from I-215) and Bundy Canyon Road near Lake Elsinore as the Temecula Valley Freeway.<ref name=caltrans63/>

Then, in 1993, the California Assembly passed legislation officially designating SR&nbsp;71 as a part of the Chino Valley Freeway.<ref>{{harvnb| California Department of Transportation |2009|p=67}}</ref> However, the "Corona Freeway" name is sometimes still applied to this portion of SR&nbsp;71; thus, despite the official change, guide signs on I-10 eastbound and SR&nbsp;57 southbound at the Kellogg Interchange in Pomona continued to refer to SR&nbsp;71 as the "Corona Freeway" until the signs were replaced some time later.

Present SR&nbsp;15 was signed after the creation of I-15 in 1968. Since I-15's southern terminus was at I-8, SR&nbsp;15 was signed mostly along 40th&nbsp;Street and '''Wabash Boulevard''' in San Diego to its merge with I-5. The portion between Adams Avenue and I-805 in City Heights remained a city street for a long time, forcing drivers to take detours or drive through city streets to get downtown. This portion was not fully completed until January&nbsp;2000, becoming one of the last freeways built in San Diego . For this reason, the freeway is sometimes referred to as the '''40th&nbsp;Street Freeway'''.<ref name="cahighways.org" />

Before the completion of the freeway, from 1968 through 1992, the San Diego neighborhood was known for prostitution, drugs, driveby shootings, and gangs. This was indirectly caused by Caltrans' plans to build a freeway in this area on land where houses were located. Because families did not want to live in these houses since they would be soon torn down, they rented them to individuals who were only going to be in the area on a temporary basis, many of whom 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&nbsp;1992 that construction began after they succeeded to evict residents to make way for it. 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.<ref name="sdut">{{cite news |first = Jeanne F. |last = Brooks |title = A Neighborhood's Rough Road: Mid City's I-15 Stretch to Open After Tortuous 40-Year Saga |work = The San Diego Union-Tribune |agency = Copley News Service |date = January 9, 2000 |id = {{ProQuest|271675995}} }}{{dead link|date=November 2011}}</ref><ref>{{Cite web |date=May 23, 2023 |title=Watch as 9+ blocks of housing in San Diego become a freeway |url=https://www.kpbs.org/news/local/2023/05/23/watch-as-9-blocks-of-housing-in-san-diego-become-a-freeway |access-date=January 25, 2025 |website=KPBS Public Media |language=en}}</ref><ref>{{Cite web |date=July 17, 2023 |title=23 years after opening of SR-15 freeway, City Heights is still trying to heal |url=https://www.kpbs.org/news/local/2023/07/17/23-years-after-opening-of-sr-15-freeway-city-heights-is-still-trying-to-heal |access-date=January 25, 2025 |website=KPBS Public Media |language=en}}</ref>

Most of I-15 has undergone major improvements from Devore to the Nevada State Line, beginning in 2002 and costing $349&nbsp;million. These improvements were designed to improve traffic flow on the heavily traveled highway for those going to and from Las Vegas. Most of the construction was completed by winter&nbsp;2009.<ref>{{cite map |publisher = California Department of Transportation |date = June 2004 |title = Interstate 15 Major Improvements from Barstow to Nevada stateline |url = http://www.dot.ca.gov/dist8/projects/15/I-15%20Brstw%20-STLN.revsd%206-2004%20copy.pdf |format = PDF |archive-url = https://web.archive.org/web/20080911032558/http://www.dot.ca.gov/dist8/projects/15/I-15%20Brstw%20-STLN.revsd%206-2004%20copy.pdf |archive-date = September 11, 2008 }}</ref> Projects include adding {{convert|39|mi|km}} of truck lanes on hills at various locations, repaving {{convert|76|mi|km}} of {{nowrap|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. The new agricultural inspection station opened in August&nbsp;2018.<ref name=cdfa>{{cite news|url=https://plantingseedsblog.cdfa.ca.gov/wordpress/?p=15935|title=CDFA opens new Border Inspection Station near Nevada border|publisher=California Department of Food and Agriculture|date=August 24, 2018|access-date=November 23, 2018}}</ref><ref name=newag>{{cite news|url=http://www.vvdailypress.com/news/20180907/caltrans-opens-new-agricultural-inspection-station-on-i-15-dismantling-old-station-in-yermo|title=Caltrans opens new Agricultural Inspection Station I-15, dismantling old station in Yermo|newspaper=Daily Press|date=September 7, 2018|access-date=October 9, 2018}}</ref>

===State Route 31=== {{Infobox road small |state=CA |type=SR |route=31 |location=Corona - Ontario |formed=1934 |deleted=1974 }} In 1933, I-15 was defined as '''Legislative Route&nbsp;193''', running from pre-1964 Legislative Route&nbsp;43 (present SR&nbsp;91) in Corona to pre-1964 Legislative Route&nbsp;9 (now SR&nbsp;66), and was extended north to pre-1964 Legislative Route&nbsp;31 (present I-15 and {{nowrap|I-215)}} in 1935.<ref name="cah LR 193">{{cite web |first = Daniel P. |last = Faigin |date = July 18, 2012 |url = http://www.cahighways.org/193-200.html#LR193 |title = Routes 193 through 200 |work = California Highways |publisher = Self-published |access-date = July 18, 2012 }} {{sps|certain=yes |date= July 2012}}</ref> The piece south of US&nbsp;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.<ref>{{cite map |author = H.M. Gousha |author-link = H.M. Gousha |url = http://members.cox.net/mkpl2/hist/map-ca1955-la.jpg |title = 1955 Gousha Los Angeles district map |publisher = H.M. Gousha |access-date = November 29, 2011 |url-status = dead |archive-url = https://web.archive.org/web/20110726003121/http://members.cox.net/mkpl2/hist/map-ca1955-la.jpg |archive-date = July 26, 2011}}</ref> This was still the only existing piece in 1963, and had a planned freeway replacement to the east.<ref>{{cite map |url = http://www.cahighways.org/maps/1963routes.jpg |title = 1963 Caltrans Los Angeles and vicinity map |access-date = November 29, 2011 }}</ref>

In the 1964 renumbering, the route was assigned as SR&nbsp;31. It was added to the Interstate Highway System in February&nbsp;1972 as a realignment of I-15 (the former alignment became I-15E). However, as soon as the reroute was made, the cities of San Bernardino and Riverside voiced concerns that this new routing, which completely bypassed their city centers, would have a negative effect on their development plans. Together, these cities devised a plan in which the new western route via Corona and Ontario would become '''Interstate&nbsp;15W''', while US&nbsp;395 would be renumbered '''Interstate&nbsp;15E''', regardless of the actual non-Interstate status of the latter route.<ref name="cah interstates">{{cite web |first = Daniel P. |last = Faigin |date = July 18, 2012 |url = http://www.cahighways.org/itypes.html |title = Interstate Highway Types and the History of California's Interstates |work = California Highways |access-date = July 18, 2012 }} {{sps|certain=yes |date= July 2012}}</ref> Legislative changes were made in 1974, eliminating SR&nbsp;31 (along with SR&nbsp;71 south of Corona) in favor of I-15W.<ref name="cah 31">{{cite web |first = Daniel P. |last = Faigin |date = July 18, 2012 |url = http://www.cahighways.org/025-032.html#031 |title = Routes 25 through 32 |work = California Highways |access-date = July 18, 2012 }}{{sps|certain=yes|date= July 2012}}</ref> However, SR&nbsp;31 continued to be signed—as temporary I-15W—until present I-15 was finished. (A 1986 map shows state maintenance continuing north past SR&nbsp;60 to Jurupa Street, where it turned east to I-15.<ref>{{cite map |url = http://www.cahighways.org/maps/1986map.jpg |title = 1986 Caltrans Los Angeles and vicinity map |access-date = November 29, 2011 }}</ref>)

==Future== The segment signed as California SR&nbsp;15 from I-5 to I-8 in San Diego is planned to be redesignated as part of I-15 once this segment is completely upgraded to Interstate standards, namely where the freeway's interchange with SR&nbsp;94 is concerned. The interchange currently has left-exits and blind merges, and is due to be updated with a long-awaited widening of both SR&nbsp;15 and SR&nbsp;94. At that time, SR&nbsp;15 is planned to be signed as part of I-15. The remaining portion of SR&nbsp;15 conforms with Interstate standards.<ref name="cahighways.org"/>

In December 2018, the San Bernardino County Transportation Authority (SBCTA) approved the final environmental document for an 8-mile section of the San Bernardino County I-15 Express Lanes Project, spanning from Cantu-Galleano Ranch Road in Riverside County to Foothill Boulevard near Rancho Cucamonga. Construction on this section of express lanes is expected to be complete by 2028.<ref>{{Cite news|title=I-15 Corridor Freight and Express Lanes Project|url=https://www.gosbcta.com/wp-content/uploads/2025/02/I-15-ExpLanes-Fact-Sheet-ENG-022025.pdf|date=2024-03-02}}</ref>

In 2020, Brightline signed a 50-year lease for use of the I-15 right-of-way between the Victor Valley and Nevada border for use in their Brightline West high-speed rail service.<ref>{{Cite news|first=Caitlin|last=Lilly|date=30 June 2020|title=XpressWest receives permission to use I-15 right-of-way in California|url=https://www.fox5vegas.com/news/xpresswest-receives-permission-to-use-i-15-right-of-way-in-california/article_ace4f210-baf1-11ea-a5ca-c77b8a76754d.html|access-date=2 July 2020}}</ref><ref name=July2020>{{Cite web|last=Sharp|first=Steven|date=2020-07-07|title=High-Speed Train to Las Vegas Takes Another Step Forward|url=https://urbanize.la/post/high-speed-train-las-vegas-takes-another-step-forward|access-date=2020-07-07|website=Urbanize LA|language=en|archive-date=July 7, 2020|archive-url=https://web.archive.org/web/20200707223710/https://urbanize.la/post/high-speed-train-las-vegas-takes-another-step-forward|url-status=dead}}</ref>

==Exit list== {{CAinttop|exit|length_ref=<ref name=calnexus/> |exit_ref=<ref name=calnexus>{{cite web |date = August 23, 2018 |first = Faizah |last = Saif |publisher = California Department of Transportation |work = California Numbered Exit Uniform System |url = https://dot.ca.gov/-/media/dot-media/programs/safety-programs/documents/exit/f0017849-15-a11y.pdf |title = Interstate 15 Freeway Interchanges |access-date = October 25, 2020}}</ref> }} {{CAint|exit |county=San Diego |cspan=56 |location=San Diego |lspan=40 |mile=0.00 |exit= |road=32nd Street to Harbor Drive |notes=At-grade intersection; southern end of SR 15 }} {{CAint|exit |mile=0.41 |exit=1A |road=Main Street |notes=Southbound exit and northbound entrance; southern end of state maintenance |type=incomplete}} {{CAint|exit |mile=0.55 |mspan=2 |exit=1B |type=incomplete |road={{Jct|state=CA|I|5|dir1=north|city1=Los Angeles}} |notes=Southbound exit and northbound entrance; I-5 exit 13A |nspan=2 }} {{CAint|exit |type=incomplete |mile=none |exit=1C |road={{Jct|state=CA|I|5|dir1=south|city1=National City|city2=Chula Vista}} |notes=none }} {{CAint|exit |mile=0.77 |exit=1D |road=Ocean View Boulevard |notes=Signed as exit 1 northbound }} {{CAint|exit |type=closed |mile=1.07 |exit= |road=Imperial Avenue |notes=Exit removed in the late 1990s to conform SR 15 with federal highway minimum spacing requirements between adjacent interchanges<ref>{{cite web |title = SR-15/IMPERIAL AVENUE RAMPS REMOVAL |url = https://ceqanet.opr.ca.gov/1996104240 |work = California Environmental Quality Act (via www.ca.gov) |date = July 12, 1996 |access-date = April 30, 2023}}</ref> }} {{CAint|exit |mile=1.85 |exit=2A |road=Market Street }} {{CAint|exit |mile=2.23 |exit=2B-C |road={{Jct|state=CA|SR|94|name1=M. L. King Jr. Freeway|road|Home Avenue}} |notes=Signed as exits 2B (east) and 2C (west) northbound; southbound exit to SR 94 east is via exit 3; SR 94 exits 2A-C }} {{CAint|exit |mile=3.37 |mspan=2 |exit=3 |espan=2 |type=incomplete |road={{Jct|state=CA|I|805|dir1=north|city1=Los Angeles}} |notes=Northbound exit and southbound entrance; I-805 south exit 14 }} {{CAint |mile=none |type=incomplete |road={{Jct|state=CA|to2=yes|I|805|CA|94|dir1=south|dir2=east}} |notes=Southbound exit and northbound entrance; I-805 north exit 14 }} {{CAint|exit |mile=4.67 |exit=5A |road=University Avenue&nbsp;– City Heights Transit Plaza |notes=}} {{CAint|exit |mile=5.05 |exit=5B |road={{jctname|state=CA|US-Hist|80|name1=El Cajon Boulevard|noshield=yes|location1=Boulevard Transit Plaza}} |notes=Former US 80 }} {{CAint|exit |mile=5.61 |exit=6A |road=Adams Avenue }} {{CAint|exit |type=trans |mile=6.13 |exit=6B |road={{jct|state=CA|I|8|location1=Beaches|city2=El Centro|road|Camino del Rio South}} |notes=Northern end of SR 15; southern end of I-15; I-8 exits 7A-B }} {{CAint|exit |mile=6.82 |exit=7 |road=Friars Road&nbsp;– Snapdragon Stadium |notes=Interchange reconfiguration project scheduled to be completed in November 2025<ref>{{cite web |title =Caltrans is adding bike lanes to a busy stretch of Friars Road |url = https://www.cbs8.com/article/news/local/caltrans-adding-bike-lanes-to-friars-road/509-75c36feb-eae4-4694-91e7-1cfb41ffe34e|website=KFMB-TV|date=October 4, 2024|access-date=May 26, 2025}}</ref> }} {{CAint|exit |mile=8.37 |exit=8 |road=Aero Drive }} {{CAint|exit |mile=9.25 |exit=9 |road=Balboa Avenue / Tierrasanta Boulevard |notes=Former eastern end of SR 274 }} {{CAint|exit |mile=10.00 |exit=10 |road=Clairemont Mesa Boulevard |notes=Southbound exit is part of exit 11 }} {{CAint|exit |mile=10.58 |exit=11 |road={{Jct|state=CA|SR|52}} |notes=Exit 7 on SR 52 }} {{CAint|exit |type=etc |mile= |exit=— |road=I-15 Express Lanes (San Diego County) |notes=Southern end of Express Lanes (unsigned SR 15S)<ref name="SR15S"/> }} {{CAint|exit |type=etc |mile= |exit=— |road={{Jct|state=CA|SR|163|dir1=south}} |notes=Express Lanes access only; southbound exit and northbound entrance }} {{CAint|exit |type=incomplete |mile=12.13 |exit=12 |road={{Jct|state=CA|SR|163|dir1=south|name1=Cabrillo Freeway}}&nbsp;– Downtown |notes=Southbound exit and northbound entrance; former US 395 south }} {{CAint|exit |mile=13.34 |exit=13 |road=Miramar Way |notes=Serves Marine Corps Air Station Miramar }} {{CAint|exit |mile=14.29 |exit=14 |road=Miramar Road / Pomerado Road |notes=Former US 395 north }} {{CAint|exit |mile=15.01 |exit=15 |road=Carroll Canyon Road }} {{CAint|exit |type=etc |mile= |exit=— |road=Hillery Drive&nbsp;– Mira Mesa |notes=Express Lanes access only }} {{CAint|exit |mile=15.93 |exit=16 |road=Mira Mesa Boulevard }} {{CAint|exit |mile=17.32 |exit=17 |road=Mercy Road / Scripps Poway Parkway }} {{CAint|exit |mile=17.82 |place=Los Peñasquitos Creek Bridge }} {{CAint|exit |mile=18.18 |exit=18 |road=Poway Road (CR S4) / Rancho Peñasquitos Boulevard }} {{CAint|exit |type=etc |mile= |exit=— |road={{Jct|state=CA|SR|56|dir1=west|road|Ted Williams Parkway}} |notes=Express Lanes access only; northbound exit and southbound entrance }} {{CAint|exit |type=etc |mile= |exit=— |road=Sabre Springs-Peñasquitos Transit Station |notes=Express Lanes access only }} {{CAint|exit |mile=19.48 |exit=19 |road={{Jct|state=CA|SR|56|dir1=west|name1=Ted Williams Freeway|road|Ted Williams Parkway}} |notes=SR 56 exit 9 }} {{CAint|exit |mile=20.58 |exit=21 |road=Carmel Mountain Road }} {{CAint|exit |mile=21.92 |exit=22 |road=Camino del Norte }} {{CAint|exit |mile=22.94 |exit=23 |road=Bernardo Center Drive }} {{CAint|exit |type=etc |mile= |exit=— |road=George Cooke Express Drive&nbsp;– Rancho Bernardo |notes=Express Lanes access only }} {{CAint|exit |mile=23.69 |exit=24 |road=Rancho Bernardo Road }} {{CAint|exit |mile=26.03 |exit=26 |road=Pomerado Road (CR S5) / West Bernardo Drive |notes=Former US 395 south }} {{CAint|exit |mile=26.20 |place=Lake Hodges Bridge }} {{CAint|exit |location=Escondido |lspan=11 |mile=26.98 |exit=27 |road=Via Rancho Parkway }} {{CAint|exit |type=etc |mile= |exit=— |road=Del Lago Boulevard / Beethoven Drive |notes=Express Lanes access only }} {{CAint|exit |mile=27.66 |exit=28 |type=incomplete |road=Centre City Parkway (I-15 Bus. north) |notes=Northbound exit and southbound entrance; former US 395 north }} {{CAint|exit |mile=28.77 |exit=29 |road=Felicita Road / Citracado Parkway }} {{CAint|exit |mile=30.10 |exit=30 |road=9th Avenue / Auto Park Way }} {{CAint|exit |mile=30.63 |exit=31 |road=Valley Parkway (CR S6)&nbsp;– Downtown Escondido }} {{CAint|exit |type=etc |mile= |exit=— |road=Hale Avenue |notes=Express Lanes access only; northbound exit and southbound entrance }} {{CAint|exit |type=etc |mile= |exit=— |road=I-15 Express Lanes (San Diego County) |notes=Northern end of Express Lanes (unsigned SR 15S)<ref name="SR15S"/> }} {{CAint|exit |mile=31.52 |exit=32 |road={{Jct|state=CA|SR|78|city1=Oceanside|city2=Ramona}} |notes=SR 78 east exit 17A-B; west exit 17 }} {{CAint|exit |mile=32.87 |exit=33 |road=El Norte Parkway }} {{CAint|exit |mile=33.92 |exit=34 |road=Centre City Parkway (I-15 Bus. south) / Country Club Lane |notes=Southbound exit and northbound entrance; former US 395 south |type=incomplete }} {{CAint|exit |location=none |mile=36.64 |exit=37 |road=Deer Springs Road (CR S12) / Mountain Meadow Road }} {{CAint|exit |location=Bonsall |lspan=2 |mile=40.85 |exit=41 |road=Gopher Canyon Road / Old Castle Road }} {{CAint|exit |mile=43.29 |exit=43 |road=Old Highway 395 |notes=Former US 395 }} {{CAint|exit |location=none |mile=46.49 |exit=46 |road={{Jct|state=CA|SR|76|city1=Pala|city2=Oceanside}} }} {{CAint|exit |location=Fallbrook |mile=50.59 |exit=51 |road=Mission Road (CR S13)&nbsp;– Fallbrook }} {{CAint|exit |county1=San Diego |county2=Riverside |location=Rainbow |mile=54.08 |exit=54 |road=Rainbow Valley Boulevard }} {{CAint|exit |county=Riverside |cspan=37 <!--|county_note=RIV R0.00-52.28--> |type=incomplete |location=none |lspan=2 |mile=55.36 |mspan=2 |place=US Border Patrol checkpoint (northbound only) }} {{CAint|exit |type=incomplete |mile=none |place=Weigh station (northbound only) }} {{CAint|exit |location=Temecula |lspan=3 |mile=57.70 |exit=58 |road={{Jct|state=CA|road|Temecula Parkway|SR|79|to2=y|dir2=south|city1=Warner Springs|city2=Indio}} |notes=Former SR&nbsp;71 south; former SR&nbsp;79 south}} {{CAint|exit |mile=59.25 |exit=59 |road=Rancho California Road / Old Town Front Street }} {{CAint|exit |mile=60.88 |exit=61 |road={{Jct|state=CA|road|Winchester Road|SR|79|to2=y|dir2=north}} |notes=Former SR&nbsp;79 north}} {{CAint|exit |location1=Temecula |location2=Murrieta |mile=61.68 |exit=62 |type=incomplete |road=French Valley Parkway |notes=Southbound exit only}} {{CAint|exit |location=Murrieta |lspan=3 |mile=63.00 |exit=63 |type=incomplete |road={{Jct|state=CA|I|215|dir1=north|name1=Escondido Freeway north|city1=Riverside|city2=San Bernardino}} |notes=Northbound exit and southbound entrance; southbound access is via exit 64; former I-15E north / US 395 north}} {{CAint|exit |mile=63.73 |exit=64 |road={{Jct|state=CA|road|Murrieta Hot Springs Road|I|215|to2=to|dir2=north|city1=Riverside}} |notes=“To I-215” not signed northbound }} {{CAint|exit |mile=64.86 |exit=65 |road=California Oaks Road / Kalmia Street }} {{CAint|exit |location=Wildomar |lspan=3 |mile=67.90 |exit=68 |road=Clinton Keith Road }} {{CAint|exit |mile=69.34 |exit=69 |road=Wildomar Trail |notes=Formerly Baxter Road<ref>{{cite web |title=Say Goodbye to Baxter Road in Wildomar: I-15 Exit Getting Renamed |url=https://patch.com/california/lakeelsinore-wildomar/say-goodbye-baxter-road-wildomar-i-15-exit-getting-renamed |website=Lake Elsinore-Wildomar Patch |date=March 4, 2020 |publisher=Patch Media |access-date=March 8, 2020}}</ref> }} {{CAint|exit |mile=70.56 |exit=71 |road=Bundy Canyon Road }} {{CAint|exit |location=Lake Elsinore |lspan=5 |mile=73.43 |exit=73 |road=Diamond Drive / Railroad Canyon Road }} {{CAint|exit |mile=75.21 |exit=75 |road=Main Street (I-15 Bus. north) }} {{CAint|exit |mile=76.54 |exit=77 |road={{Jct|state=CA|SR|74|name1=Central Avenue|city1=San Juan Capistrano|city2=Perris}} }} {{CAint|exit |mile=78.12 |exit=78 |road=Nichols Road }} {{CAint|exit |mile=80.95 |exit=81 |road=Lake Street (I-15 Bus. south) }} {{CAint|exit |location=Temescal Valley |lspan=2 |mile=84.67 |exit=85 |road=Indian Truck Trail }} {{CAint|exit |mile=87.54 |exit=88 |road=Temescal Canyon Road |notes=Former SR 71 }} {{CAint|exit |location=Corona |lspan=9 |mile=89.91 |exit=90 |road=Weirick Road / Dos Lagos Drive }} {{CAint|exit |mile=91.08 |exit=91 |road=Cajalco Road }} {{CAint|exit |type=etc |mile= |exit=— |road=I-15 Riverside Express Lanes |notes=Southern end of Express Lanes }} {{CAint|exit |mile=92.08 |exit=92 |road=El Cerrito Road }} {{CAint|exit |mile=92.96 |exit=93 |road=Ontario Avenue |notes=Former SR 71 }} {{CAint|exit |mile=94.62 |exit=95 |road=Magnolia Avenue }} {{CAint|exit |type=etc |mile= |exit=— |road={{Jct|state=CA|SR-Express|91|dir1=west}} |notes=Express Lanes access only }} {{CAint|exit |mile=95.77 |exit=96A |road={{Jct|state=CA|SR|91|dir1=west|name1=Riverside Freeway|city1=Beach Cities}} |notes=Signed as exit 96 northbound; former US 91; SR 91 exit 51 |nspan=2 }} {{CAint|exit |mile=95.77 |exit=96B |road={{Jct|state=CA|SR|91|dir1=east|name1=Riverside Freeway|city1=Riverside}} |notes=none }} {{CAint|exit |location1=Corona |location2=Norco |mile=97.14 |exit=97 |road=Hidden Valley Parkway |notes=Formerly Yuma Drive<ref>{{cite web |title = Corona Avenue and Valley View Avenue Street |url = https://ceqanet.opr.ca.gov/2001041032/2 |work = California Environmental Quality Act via CEQAnet Web Portal |date = December 26, 2001 |access-date = May 14, 2022}}</ref> }} {{CAint|exit |location=Norco |lspan=2 |mile=97.90 |exit=98 |road=Second Street (I-15 Bus. north) }} {{CAint|exit |mile=99.87 |exit=100 |road=Sixth Street (I-15 Bus. south) }} {{CAint|exit |location1=Eastvale |location2=Jurupa Valley |lspan=6 |mile=102.53 |exit=103 |road=Limonite Avenue }} {{CAint|exit |mile=104.62 |exit=105 |road=Cantu-Galleano Ranch Road }} {{CAint|exit |type=etc |mile= |exit=— |road=I-15 Riverside Express Lanes |notes=Northern end of Express Lanes }} {{CAint|exit |type=unbuilt |mile= |exit=— |road=I-15 San Bernardino Express Lanes (Phase 1) |notes=Southern end of express lanes-under construction; planned to open in 2028<ref name="SB Express Lanes Phase 1"/> }} {{CAint|exit |mile=105.74 |exit=106A |road={{Jct|state=CA|SR|60|dir1=east|name1=Pomona Freeway|city1=Riverside}} |notes=SR 60 east exit 41, west exit 41B |nspan=2 }} {{CAint|exit |mile=105.74 |exit=106B |road={{Jct|state=CA|SR|60|dir1=west|name1=Pomona Freeway|city1=Los Angeles}} |notes=none }} {{CAint|exit |county=San Bernardino |cspan=72 <!--|county_note=SBD 0.00-186.24--> |location=Ontario |lspan=3 |mile=107.56 |exit=108 |road=Jurupa Street / Auto Center Drive |notes=Former SR 31 south}} {{CAint|exit |mile=108.94 |exit=109A |road={{Jct|state=CA|I|10|dir1=west|name1=San Bernardino Freeway|city1=Los Angeles}} |notes=former US 99; I-10 east exits 58A-B; west exit 58 |nspan=2 }} {{CAint|exit |mile=108.94 |exit=109B |road={{Jct|state=CA|I|10|dir1=east|name1=San Bernardino Freeway|city1=San Bernardino}} |notes=none }} {{CAint|exit |location=Rancho Cucamonga |lspan=3 |mile=109.60 |exit=110 |road=4th Street }} {{CAint|exit |mile=111.85 |exit=112 |road={{Jct|state=CA|SR|66|name1=Foothill Boulevard}} |notes=Former US 66}} {{CAint|exit |type=unbuilt |mile= |exit=— |road=I-15 San Bernardino Express Lanes (Phase 1) |notes=Northern end of express lanes-under construction; planned to open in 2028<ref name="SB Express Lanes Phase 1"/> }} {{CAint|exit |location1=Rancho Cucamonga |location2=Fontana |lspan=3 |mile=113.26 |exit=113 |road=Base Line Road }} {{CAint|exit |mile=114.64 |exit=115A |road={{Jct|state=CA|SR|210|dir1=east|name1=Foothill Freeway|city1=San Bernardino}} |notes=Signed as the reverse southbound; SR 210 exit 64A; future I-210 |nspan=2 }} {{CAint|exit |mile=114.64 |exit=115B |road={{Jct|state=CA|SR|210|dir1=west|name1=Foothill Freeway|city1=Pasadena}} |notes=none }} {{CAint|exit |location=Fontana |lspan=2 |mile=116.20 |exit=116 |road=Summit Avenue }} {{CAint|exit |lspan=3 |mile=117.58 |exit=118 |road=Duncan Canyon Road |notes= }} {{CAint|exit |location1=Fontana |location2=Rialto |mile=119.39 |exit=119 |road=Sierra Avenue }} {{CAint|exit |location=none |mile=122.20 |exit=122 |road=Glen Helen Parkway }} {{CAint|exit |location=San Bernardino |lspan=5 |mile=122.92 |mspan=4 |exit=123 |type=incomplete |road={{Jct|state=CA|I|215|dir1=south|name1=Barstow Freeway south|road|Devore Road}} |notes=Northbound signage; former I-15E / US 91 / US 395 south / US 66 west; I-215 north exit 54B}} {{CAint|exit |mile=none |exit=— |type=incomplete |road={{Jct|state=CA|I-Truck|15|dir1=north|nolink1=y|road|Kenwood Avenue}} |notes=South end of truck bypass}} {{CAint|exit |mile=none |exit=123 |type=incomplete |road={{Jct|state=CA|I|215|dir1=south|name1=Barstow Freeway south|city1=San Bernardino|city2=Riverside}} |notes=Southbound signage; former I-15E / US 91 / US 395 south / US 66 west}} {{CAint|exit |mile=none |exit=— |type=incomplete |road={{Jct|state=CA|I-Truck|15|dir1=south|nolink1=y}} |notes=North end of truck bypass}} {{CAint|exit |mile=124.10 |exit=124 |type=incomplete |road=Kenwood Avenue |notes=Southbound signage}} {{CAint|exit |location=none |mile=129.15 |exit=129 |road=Cleghorn Road |notes= }} {{CAint|exit |location=none |mile=130.00 |place=Weigh station }} {{CAint|exit |location=none |mile=130.51 |exit=131 |road={{Jct|state=CA|SR|138|city1=Palmdale|location2=Silverwood Lake}} |notes= }} {{Jctplace|exit |state=CA |location=none <!--|postmile=R26.00--> |mile=135.33 |place=Cajon Summit, elevation {{Convert|4260|ft}}<ref name=summitlist>{{cite web|publisher=California Department of Transportation|title=Elevation and Location of Summits and Passes in California|url=http://www.dot.ca.gov/hq/tsip/data_library/archives/summit.xls|url-status=dead|archiveurl=https://web.archive.org/web/20170301032752/http://www.dot.ca.gov/hq/tsip/data_library/archives/summit.xls|archivedate=March 1, 2017}}</ref> }} {{CAint|exit |location=Hesperia |lspan=5 |mile=137.76 |exit=138 |road=Oak Hill Road }} {{CAint|exit |mile=139.53 |exit=140 |road=Ranchero Road }} {{CAint|exit |mile=141.47 |mspan=2 |exit=141 |espan=2 |type=incomplete |road={{Jct|state=CA|US|395|dir1=north|city1=Bishop|city2=Adelanto}} |notes=Northbound exit and southbound entrance; southern end of US 395}} {{CAint |mile=none |type=incomplete |road={{Jct|state=CA|road|Joshua Street|US|395|to2=yes|dir2=north}} |notes=Southbound exit and northbound entrance}} {{CAint|exit |mile=143.14 |exit=143 |road=Main Street&nbsp;– Hesperia, Phelan }} {{CAint|exit |location1=Hesperia |location2=Victorville |mile=146.73 |exit=147 |road=Bear Valley Road&nbsp;– Lucerne Valley }} {{CAint|exit |location=Victorville |lspan=7 |mile=147.96 |exit=148 |road=La Mesa Road / Nisqualli Road |notes=}} {{CAint|exit |mile=149.65 |exit=150 |type=concur |road={{Jct|state=CA|SR|18|dir1=west|name1={{jct|state=CA|road|Palmdale Road|BL|15|dab2=Victorville|dir2=north|US-Hist|66|dir3=east|noshield=yes}}}} |notes=Southern end of SR&nbsp;18 overlap; former US&nbsp;66 east / US&nbsp;91 north}} {{CAint|exit |mile=150.57 |exit=151A |road=Roy Rogers Drive }} {{CAint|exit |mile=151.17 |exit=151B |road=Mojave Drive }} {{CAint|exit |mile=152.63 |exit=153A |type=concur |road={{Jct|state=CA|SR|18|dir1=east|name1={{jct|state=CA|road|D Street|BL|15|dab2=Victorville|dir2=south|US-Hist|66|noshield=yes}}|city1=Apple Valley}} |notes=Northern end of SR 18 overlap; former US&nbsp;66 / US&nbsp;91}} {{CAint|exit |mile=152.71 |exit=153B |type=incomplete |road=E Street |notes=Northbound exit and entrance }} {{CAint|exit |mile=153.54 |exit=154 |road=Stoddard Wells Road }} {{CAint|exit |location=Apple Valley |lspan=2 |mile=156.65 |exit=157 |road=Stoddard Wells Road&nbsp;– Bell Mountain }} {{CAint|exit |mile=161.25 |exit=161 |road=Dale Evans Parkway&nbsp;– Apple Valley }} {{CAint|exit |location=none |mile=165.10 |exit=165 |road=Wild Wash Road }} {{CAint|exit |location=none |mile=169.30 |exit=169 |road=Hodge Road }} {{CAint|exit |location=Barstow |lspan=8 |mile=174.98 |exit=175 |road=Outlet Center Drive }} {{CAint|exit |mile=177.91 |exit=178 |road=Lenwood Road }} {{CAint|exit |mile=179.25 |exit=179 |road={{Jct|state=CA|SR|58|dir1=west|city1=Bakersfield}} |notes=SR 58 east exit 234 to I-15 south, no exit number to I-15 north }} {{CAint|exit |mile=180.76 |exit=181 |road={{jctname|state=CA|BL|15|dab1=Barstow|dir1=east|name1=L Street|CR|66|dab2=San Bernardino|name2=West Main Street|noshield=yes}} }} {{CAint|exit |mile=182.69 |exit=183 |road={{Jct|state=CA|SR|247|dir1=south|name1=Barstow Road}} }} {{CAint|exit |mile=183.56 |exit=184A |road={{Jct|state=CA|I|40|dir1=east|city1=Needles}} |notes=Northbound exit and southbound entrance; southbound access is via exit 184; western terminus of I-40 |type=incomplete }} {{CAint|exit |mile=184.09 |exit=184B |road={{jct|state=CA|road|East Main Street (I-15 Bus. / CR 66)|to2=To|I|40|city1=Needles}} |notes=Signed as exit 184 southbound; “to I-40” not signed northbound; former US 66}} {{CAint|exit |mile=186.03 |exit=186 |road=Old Highway 58 west |notes=Former US 91 south/US 466/SR 58 west }} {{CAint|exit |location=none |mile=188.74 |exit=189 |road=Fort Irwin Road |notes=Serves Fort Irwin }} {{CAint|exit |location=none |mile=190.98 |exit=191 |road=Ghost Town Road |notes=Serves the ghost town of Calico }} {{CAint|exit |location=Yermo |lspan=2 |mile=193.78 |exit=194 |road=Calico Road&nbsp;– Yermo, Calico}} {{CAint|exit |mile=195.52 |exit=196 |road=Yermo Road&nbsp;– Yermo}} {{jctplace|exit |location=none |type=closed |mile=196.00 |mile2=196.50 |place=Agricultural Inspection Station (closed; was southbound only) }} {{CAint|exit |location=none |mile=197.63 |exit=198 |road=Minneola Road }} {{CAint|exit |location=none |mile=205.55 |exit=206 |road=Harvard Road }} {{CAint|exit |location=none |mile=212.78 |exit=213 |road=Field Road }} {{jctplace|exit |state=CA |location=none |mile=216.76 |exit=217 |restarea=Clyde V. Kane Rest Area (Exit 217) }} {{CAint|exit |location=none |mile=220.73 |exit=221 |road=Afton Road }} {{CAint|exit |location=none |mile=229.57 |exit=230 |road=Basin Road }} {{CAint|exit |location=none |mile=233.38 |exit=233 |road=Rasor Road }} {{CAint|exit |location=none |mile=239.32 |exit=239 |road=Zzyzx Road&nbsp;– Zzyzx }} {{CAint|exit |location=Baker |lspan=3 |mile=244.95 |exit=245 |type=incomplete |road=Baker Boulevard (I-15 Bus. north)&nbsp;– Baker |notes=Northbound exit and southbound entrance; former US 91 north / US 466 east}} {{CAint|exit |mile=245.72 |exit=246 |road={{Jct|state=CA|SR|127|dir1=north|road|Kelbaker Road|city1=Death Valley}} }} {{CAint|exit |mile=247.60 |exit=248 |type=incomplete |road=Baker Boulevard (I-15 Bus. south)&nbsp;– Baker |notes=Southbound exit and northbound entrance; former US 91 south / US 466 west}} {{CAint|exit |location=none |mile=258.75 |exit=259 |road=Halloran Springs Road }} {{CAint|exit |location=none |mile=264.71 |exit=265 |road=Halloran Summit Road }} {{jctplace|exit |state=CA |location=none |mile=270.29 |exit=270 |restarea=Valley Wells Rest Area (Exit 270)}} {{CAint|exit |location=none |mile=271.88 |exit=272 |road=Cima Road }} {{CAint|exit |location=none |mile=280.61 |exit=281 |road=Bailey Road }} {{CAint|exit |location=none |mile=285.60 |exit=286 |road=Nipton Road }} {{jctplace|exit |location=none |type=incomplete |mile= |mile2= |place=Agricultural Inspection Station (southbound only); opened in 2018<ref name=cdfa /><ref name=newag /> }} {{CAint|exit |location=none |mile=290.54 |exit=291 |road=Yates Well Road }} {{CAint|exit |location=none |mile=295.37 |road={{jct|state=NV|I|15|dir1=north|city1=Las Vegas}} |notes=Continuation into Nevada}} {{Jctbtm|exit|keys=etc,closed,concur,incomplete,unbuilt,trans}}

==Related routes== I-215 is the only auxiliary Interstate Highway associated with I-15 in California. It is a bypass of I-15, running between Murrieta and San Bernardino. I-215 connects the city centers of both Riverside and San Bernardino, while I-15 runs to the west through Corona and Ontario.

Business routes of Interstate 15 exist in Escondido, Lake Elsinore, Norco, Victorville, Barstow, and Baker.

==See also== *{{portal-inline|California Roads}}

==Notes== {{Reflist|group=lower-alpha}}

==References== {{Reflist}}

==External links== {{Commons category|Interstate 15 in California}} {{Attached KML|display=title,inline}} {{CASR external links|I|15}} *{{Official website|https://www.myfastrak.511sd.com|name=SANDAG FasTrak}} – includes toll information on the San Diego County Express Lanes and the other San Diego Area toll facilities *{{Official website|https://www.riversideexpress.com/ |name=Riverside County Express Lanes}} *[https://www.aaroads.com/interstate-guide/i-015/ Interstate 15 @ Interstate-Guide.com]

{{state detail page browse|type=I|route=15|state=California|stateafter=Nevada}}

{{DEFAULTSORT:I15 in California}} Category:Barstow, California California 15 Category:Mojave Desert Interstate 15 Interstate 15 Interstate 15 015 Category:U.S. Route 66 in California