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State Route 66

Click here for a key to the symbols used. An explanation of acronyms may be found at the bottom of the page.


Routing Routing

Rte 66 in 2018 / U.S. 66 in 1962(a) Route 66 is from:

(1) Route 210 near San Dimas to the eastern city limit of the City of Pomona.

(2) The eastern city limit of the City of Rialto to Route 215 in San Bernardino.

(b) The relinquished former portions of Route 66 within the city limits of the Cities of Claremont, Fontana, Rancho Cucamonga, Rialto, and Upland are not state highways and are not eligible for adoption under Section 81. For the portions of Route 66 relinquished under this section, the Cities of Claremont, Fontana, Rancho Cucamonga, Rialto, and Upland shall maintain within their respective jurisdictions signs directing motorists to the continuation of Route 66 and ensure the continuity of traffic flow on the relinquished portions of Route 66, including any traffic signal progression.

Post 1964 Signage History Post 1964 Signage History

As defined in 1963, this route ran from Route 30 near San Dimas to San Bernardino. The portions of "US 66" W of Route 30 were part of Route 248.

US 66 remained signed over the corridor of California Route 66 (and Route 248) until the completion of I-40 in the Bristol Mountains during 1972. Route 66 (with California signage) appears signed as a State Highway for the first time on the 1975 Caltrans Map. 

In 1986, Chapter 928 changed the terminus of the route to be Route 215 in San Bernardino.

In 1999, this was changed to start at Route 210 instead of Route 30, reflecting the 1998 renaming of Route 30 (AB 1650, Ch 724, 10/10/99). This route is not signed in Los Angeles County.

In 2002, both SB 246 and SB 857 changed the definition of the route (perhaps without realizing it) from "Route 210 near San Dimas" to "Route 30 in La Verne". (Yes, Route 30— I guess the fact checkers were asleep).

In 2002, SB 246 (Chapter 248, 8/26/2002) permitted the portion of Route 66 in the City of Rancho Cucamonga to be relinquished to the city. However, the city was required to ensure the continuity of traffic flow on the relinquished portion of Route 66, including any traffic signal progressions, and to maintain signs directing motorists to the continuation of Route 66. That change was also captured by SB 857 (Chapter 251, 8/26/2002), which also placed similar requirements on the city of Fontana.

The Rancho Cucamonga portions were considered for relinquishment in April 2003 and again in May 2003: 08-SBd-66-PM 4.1/10.9 Route 66 in the City of Rancho Cucamonga.

In 2006, AB 3030 (Chapter 507, 9/27/2006) permitted the relinquishment of the portion of Route 66 in the City of Upland. This segment was up for the relinquishment by the CTC in December 2007.

In 2008, SB 1366 (Chapter 717, 9/30/2008) permitted the relinquishment of the portion of Route 66 in the City of Rialto. It also changed the origin of the route: Route 210 in La Verne near San Dimas

In April 2009, the CTC relinquished right of way in the city of Rialto on Route 66, under terms and conditions as stated in Amendment No. 1 to Relinquishment Agreement No. 1419, dated March 16, 2009, determined to be in the best interest of the State. Authorized by Chapter 717, Statutes of 2008, which amended Section 366 of the Streets and Highways Code.

In 2010, SB 993 (Chapter 499, 9/28/2010) changed the definition again to indicate portions of the route that have been relinquished or that have been authorized to be relinquished, including adding relinquishment to the City of Claremont that portion of Route 66 within its city limits or sphere of influence under specified conditions. This split the route into two segments, with a continuous relinquishment between the Los Angeles-San Bernardino county line at the western city limit of the City of Upland and the eastern city limit of the City of Fontana near Maple Avenue. Subsections (b) and (c) were also reworded; the previous (b) was:

(b) (1) Notwithstanding subdivision (a), the commission may relinquish to the City of Fontana, the City of Rancho Cucamonga, the City of Rialto, and the City of Upland the respective portion of Route 66 that is located within the city limits or the sphere of influence of each city, upon terms and conditions the commission finds to be in the best interests of the state. (2) A relinquishment under this subdivision shall become effective immediately following the recordation by the county recorder of the relinquishment resolution containing the commission's approval of the terms and conditions of the relinquishment. (3) On and after the effective date of the relinquishment, both of the following shall occur: (A) The portion of Route 66 relinquished under this subdivision shall cease to be a state highway. (B) The portion of Route 66 relinquished under this subdivision may not be considered for future adoption under Section 81. (c) The city shall ensure the continuity of traffic flow on the relinquished portion of Route 66, including any traffic signal progression. (d) For relinquished portions of Route 66, the city shall maintain signs directing motorists to the continuation of Route 66.

In September 2012, AB 2679, Chapter 769 adjusted the words of the legislative definition to acknowledge the relinquishment in Rialto.

In May 2012, it was reported that the Claremont City Council members unanimously approved an agreement with Caltrans that resulted in Claremont assuming ownership of Foothill within city limits. The process took 10 years. In February 2011, the city and Caltrans negotiated an agreement to settle the relinquishment of $5.7 million needed to maintain the street. Funding was just identified. The allocation of the money must occur at the state Transportation Commission meeting in June or the funding will be lost, which is why the item came up at a council meeting in May 2012. The money will go toward a host of upgrades. Annual routine maintenance will cost $120,000, which will be funded with gas tax funds. When the $5.7 million is received, there will be $200,000 worth of work done within six months to make improvements required by the Americans with Disabilities Act and to correct traffic safety conditions. One of the first projects will be modifying a street signal at Mountain Avenue. The area has a high accident rate because of left-turn issues.

In June 2012, the CTC relinquished right of way in the city of Claremont on Route 66 between the city limits of Pomona and Upland, under terms and conditions as stated in the relinquishment agreement dated May 25, 2012, determined to be in the best interest of the State. Authorized by Chapter 499, Statutes of 2010, which amended Section 366 of the Streets and Highways Code.

In 2013, Chapter 525 (SB 788, 10/9/13) clarified the definition yet again to reflect relinquishments:

(a) Route 66 is from:

(1) Route 210 near San Dimas to the eastern city limit of the City of Pomona the Los Angeles-San Bernardino county line at the western city limit of the City of Upland.

(2) The eastern city limit of the City of Rialto Fontana near Maple Avenue to Route 215 in San Bernardino.

(b) The relinquished former portions of Route 66 within the city limits of the Cities of Claremont, Fontana, Rancho Cucamonga, Rialto, and Upland are not state highways and are not eligible for adoption under Section 81. For the portions of Route 66 relinquished under this section, the Cities of Claremont, Fontana, Rancho Cucamonga, Rialto, and Upland shall maintain within their respective jurisdictions signs directing motorists to the continuation of Route 66 and ensure the continuity of traffic flow on the relinquished portions of Route 66, including any traffic signal progression.

(c) (1) Notwithstanding subdivision (a), the commission may relinquish to the City of Claremont the respective portion of Route 66 that is located within the city limits or the sphere of influence of each city, upon terms and conditions the commission finds to be in the best interests of the state.

(2) A relinquishment under this subdivision shall become effective immediately following the recordation by the county recorder of the relinquishment resolution containing the commission's approval of the terms and conditions of the relinquishment.

(3) On and after the effective date of the relinquishment, both of the following shall occur: (A) The portion of Route 66 relinquished under this subdivision shall cease to be a state highway. (B) The portion of Route 66 relinquished under this subdivision may not be considered for future adoption under Section 81.

(4) The City of Claremont shall ensure the continuity of traffic flow on the relinquished portion of Route 66, including any traffic signal progression.

(5) For the relinquished portion of Route 66, the City of Claremont shall maintain signs directing motorists to the continuation of Route 66.

History and Signage Information History and Signage Information

Discussion Note: Unlike most of the discussions on this site, the discussion below moves from East to West. This is primarily because most discussions of Route 66 run it from Chicago to Los Angeles, as that was the primary direction of travel. In terms of postmiles (i.e., the STATUS section), however, the discussion goes in postmile order, from West to East.

US Highway Shield National Old Trails Road Sign The brief routing statement doesn't do this route justice, for it is what is left of old US 66. US 66 began its life as US 60, in the original 1926 US highways plan. It entered the state at Topock AZ, and extended westward through Barstow to San Bernardino and Los Angeles, ending in Santa Monica.

In April of 1912 the National Old Trails Road ("NOTR") was organized with the goal of signing a trans-continental highway between Baltimore and Los Angeles. Building a modern road for automotive use through the Mojave Desert of California would prove to be particularly difficult as State Highway Maintenance didn't exist and the general path of travel was alongside the service routes of railroads. The first Auto Trail through Cajon Pass was the Santa Fe-Grand Canyon Needles National Highway which was first signed in Cajon Pass by 1913. NOTR organizers later adopted the routing of the Santa Fe-Grand Canyon Needles National Highway in the western United States by 1914. The NOTR was able secure funding to pave the route through Cajon Pass and construct the 1914 Crowder Canyon Bridge. In 1916 Second State Highway Bond Act authorized a new State Highway between San Bernardino north to Barstow which would incorporate the NOTR over Cajon Pass. This new State Highway was known as LRN 31.
(Source: Gribblenation Blog: Cajon Pass; Cajon Pass Toll Road, National Old Trails Road, US Route 66/91/395 and Interstate 15)

In 1928, it was formally renumbered as US 66, and defined as the route from Los Angeles through San Fernando (which might have been a typo in CHPW), San Bernardino, Victorville, Barstow, Ludlow, Daggett, to the Arizona-California state line just W of Topock AZ. In general, this routing ran to Needles along LRN 58 (defined in 1919). The route was along the National Trails Highway, Park Moabi Road, File Mile Station Road, and Front St./Broadway in Needles. It then ran along Goffs Road through Arrowhead Junction and Goffs, and connected with the "National Trails Highway" through Essex, Amboy, and Newberry to Daggett (this was also LRN 58). In 1931, the alignment ran along Mt. Springs Road to the National Trails Highway. This route has since been bypassed by I-40, and a number of the original roads are signed as Historic US 66 or as State Route 66. Moving from East to West....

66 Colorado BridgeIn 1947, the Department of Highways moved Route 66 to a new alignment and a new bridge across the Colorado River. The movement to the Red Rock Bridge permitted elimination of one of the narrowest and crookedest portions of US 66. The cost to move to the Red Rock Bridge was only $147K, of which $71.5K was spent replacing the rail deck of the bridge, $70.5K was spent widening the old railroad approach, and $5K was spent to connect it to the existing US 66. The opportunity to replace the bridge arose when ATSF obtained approval to build a new RR bridge 500' upstream in 1942. The Red Rock bridge was set to be scrapped for its steel, but the Army was interested in the bridge and analysis showed that the need for steel would be over before the scrapping could occur. Negotiations were reopened, and the bridge was finally donated to the states in 1944. The history of the bridge going back to Civil War days may be found in the July/August 1947 issue of CHPW. Note that an act of Congress in December 1944 was required to confirm that ATSF could transfer the bridge. The old bridge was completed in 1916, and had a load limit of 11 tons. The construction of Parker Dam also served to submerge the steel supports of the old bridge. The new bridge was designed to support 94 ton trains. Note that it appears that the both the old bridge and the Red Rock bridge (or at least their locations) are still in use as of 2013 -- the Red Rock Bridge still appears to be supporting the traffic of I-40 (although it may have been rebuilt -- it still is in the correct location with respect to the RR bridge), and the original 1916 bridge appears to now be supporting a pipeline.

In 2010, the National Park Service provided $65,000 in funding to the California Preservation Foundation to hire a consultant to begin documentation of the California's portion of the Route 66 corridor. The consultant will travel the Route 66 corridor from the Arizona border at Topock to Santa Monica and catalog the different roadside properties, such as diners, motels and attractions, and identify historic themes and key periods of significance. A chief goal for the consultant will be to complete at least one nomination for the National Register of Historic Places.

From Ludlow, US 66 ran along Curcero Road, National Old Tails Highway, Lavic Road, National Old Trails Highway (again) throug Newberry Springs, and then into Barstow along E. Main Street.

In Amboy, the current "Historic US 66" is along the National Old Trails Highway. However, where the motel and gas station in Amboy sit is the second incarnation of the route. To find the original, travelers must mosey about 200 yards south, to a gravel road behind a church that passes an old graveyard.

In 1928, the first new alignment of US 66 in California was constructed, from Daggett to 1 mi E of Newberry. Dillon and Boles were awarded a $294,004 contract for construction, grading, and an oil rock surface. This included an agricultural inspection station in Daggett, CA.
(Source: FB Post by Mike Boultinghouse, 9/17/2019)

In Barstow, the route ran along Main Street.

From Barstow, US 66 ran cosigned with US 91 through Victorville and Cajon into San Bernardino. This segment was LRN 31, and corresponds to the present-day "National Trails Highway", D Street in Victorville, 7th Street in Victorville, and I-15 over the summit. It has been bypassed by present-day I-15 to Devore, and I-215 to San Bernardino. This section was defined in 1915. From 10 mi N of Cajon into San Bernardino, it was also cosigned with US 395. Note that from the Cleghorn Exit off I-15 to the Kenwood Avenue Exit, it ran along Cajon Blvd. It once again left the I-15 route (as Cajon Blvd again) at the Devore Road exit, running to Mt. Vernon Ave in San Bernardino.

Mojave TrailsIn February 2016, it was noted that there was an effort in place to bring more visibility to Historic Route 66. an effort to create three national monuments in the high desert was brought to a successful conclusion. One of these was the Mojave Trails monument, which preserves the most pristine, undeveloped remaining stretch of historic Route 66. In 2008, the World Monuments Fund designated Route 66, along with such world heritage sites as Machu Picchu and Shanghai, as a threatened resource on their Watch List of 100 Most Endangered Sites. The monument protects a number of stretches of us 66 between Needles and Barstow (as well as portions of US 95). The proclamation creating the monument noted:
(Source: Andy3175 @ AAroads, 2/14/2016; LATimes, 2/11/2016)

The Mojave Trails area has been a critical travel corridor for millennia, linking the Pacific Coast to the deserts of the southwest and beyond. The Mojave Indian Trail is the earliest known travel route passing through the Mojave Trails area, used by Native Americans for thousands of years and by early Spanish explorers and traders. In 1829, Mexican explorer Antonio Armijo pioneered the Old Spanish Trail through this area. Evidence of the trail, now designated a National Historic Trail, can still be found at Afton Canyon.

By the end of the 19th century, transcontinental rail travel had changed the American West in profound ways. In 1882, Southern Pacific constructed a railroad route from Barstow to Needles. In addition to the major rail stops established at Needles and Barstow, several smaller towns and rail stops were established along this stretch, including the alphabetically named Amboy, Bristol, Cadiz, Danby, Essex, Fenner, and Goffs. These towns remain, some as inhabited hamlets and others as abandoned ghost towns, and some historical artifacts from the original rail line still exist, including original rail ties and track and later improvements of communications poles, insulators, and wires.

A modest dirt road -- an original trackside component of the railroad project -- would later become the most famous highway in America. In 1911, in the infancy of the automobile era, the County of San Bernardino paved the first stretch of that road from Barstow to Needles. The next year, this stretch became part of the National Old Trails Road, which extended more than 3,000 miles from New York, New York, to Los Angeles, California, and connected the American coasts by pavement for the first time. In 1926, the road was officially designated as U.S. Highway 66, a designation soon known around the world as Route 66. During the 1930s, Route 66 became an important route for migrants escaping economic hardships of the Great Depression and droughts in the Central plains. As the national economy rebounded following World War II, Americans took to the highways in unprecedented numbers. The road became an American icon, earning the nickname the "Main Street of America" and inspiring popular culture through music, literature, and film.

The popularity of Route 66, however, hastened its downfall; increasing traffic quickly exceeded its two-lane capacity. In 1985, Route 66 was officially decommissioned, leaving behind a powerful albeit fragmented narrative history of America's automobile culture of the first half of the 20th century and its legacy of related commerce and architecture. The Mojave Trails area contains the longest remaining undeveloped stretch of Route 66, offering spectacular and serene desert vistas and a glimpse into what travelers experienced during the peak of the route's popularity in the mid-20th century. Today, the ghost towns along this stretch of Route 66 are a visual legacy of how the automobile shaped the American landscape.

In July 2016, it was reported that a mural on Main Street in Barstow that featured painted wooden figures of notable celebrities who have passed through Barstow along Route 66 was damaged (and hence will soon receive a face-lift). The vandals damaged its standing wooden portion. The mural is painted on the eastside portion of the Barstow Office Supply building owned by Fred and Sandy Baca, located at 613 E. Main St.. Sandy Baca said she noticed the mural had been damaged while driving home from church on June 26.
(Source: Desert Dispatch, 7/6/2016)

In October 2016, it was reported that construction of eight classic-car-themed Route 66 signs was beginning in November 2016 in Barstow, California. The signs will place vehicles popular on Route 66 during the 1950s through the 1970s on a masonry base. The seven-foot-tall signs will light at night, using solar energy. The project will cost the city $111,360. The signs are part of a plan approved earlier this summer for Barstow’s Route 66 corridor — including 1950s color schemes — to encourage businesses to be more attractive to Route 66 tourists. Colors in the plan include 1950s hues such as aqua blue, grass green, hot-rod red, lemon yellow, dusk blue, flamingo pink, sunset orange, toast brown, turquoise, avocado green and stone gray. The plan also encourages historic preservation where applicable. The plan suggests retro-themed new signs, Googie architecture, old-school facades, more public art, and drought-tolerant trees to bring shade from the desert sun for pedestrians.
(Source: Route 66 News, 10/28/2016)

In August 2017, it was reported that a Route 66 enthusiast, with the help of a gardening group, plans to plant 3,200 trees along Route 66 to honor veterans, including more than 100 in Barstow, California. Funded by a $1 million grant from CalFire, the multi-year project will honor military vets by planting over 3,000 trees along sections of Route 66 in the county. “In essence, each tree will honor a veteran in our community,” IEGC Director Mary Petit said during Monday’s City Council meeting. The trees, which Conkle said will be primarily oak trees with other varieties, will include a memorial for local veterans that consists of a concrete box embedded into the ground. A dog tag with the name, rank, branch of military and years of service will be inside the box, Conkle said, while a second dog tag will be given to the veteran or veteran’s family. A GPS device will also be included. The first tree planting along Route 66 will take place in September 2017 in Fontana, California. Conkle told the newspaper he wants the Barstow planting to coincide when the Military Vehicle Preservation Association rolls into town Oct. 11 during its Route 66 convoy. The entire Route 66 tree-planting project is projected to take about three years, although that’s dependent on funding.
(Source: Route 66 News, 8/28/2017)

Reconnecting old 66 along Cajon BlIn October 2015, it was reported that an interchange project at I-15 and I-215 that will reconnect old Route 66 in San Bernardino County is ahead of schedule for its projected completion of mid-2016. This will result in about two miles of old Route 66 in the Cajon Pass being reopened to traffic for the first time in decades. Commuters driving on Route 66 near the interchange will no longer face a gap in the historic roadway from Kenwood Avenue to Devore Road. Motorists should find less congestion along the old Route 66. Caltrans isn’t reconnecting old Route 66 entirely out of the good of its heart. The road will serve as an alternate route for when the freeway is closed because of an accident.
(Source: Route 66 News, 10/17/2015)

In San Bernardino, US 66 left US 91 and US 395 (now I-215) and headed west along the present day Route 66 along 5th Street and Foothill Blvd. This was LRN 9. In terms of freeways, this route has been bypassed by I-10. This section was defined in 1909. The history of the route in the Cajon Pass is discussed under I-15.

See the Gribblenation Blog at Cajon Pass; Cajon Pass Toll Road, National Old Trails Road, US Route 66/91/395 and Interstate 15 for detailed maps of the various routings of the highways that would become both I-15 and Route 138 in the Cajon Pass.

Route 66 currently terminates near the Foothill Freeway, I-210 (by 1963, LRN 240, duplicated by LRN 9). The original US 66 routing continued westward along Foothill, Alosta, Foothill (starting up again W of Glendora), Huntington, and Colorado Blvds. (LRN 9 along Foothill, and LRN 161 along Huntington). LRN 9 was defined in 1909. LRN 161 was defined in 1933, and LRN 240 was defined in 1959. After LRN 161 was defined, the parallel portion of LRN 9 was used for Route 118.

Note that there are true US 66 signs in Rialto, Rancho Cucamonga, and San Bernardino; specifically at the intersections with Mt. Vernon Avenue, Riverside Avenue, Citrus Avenue, Cherry Avenue, Etiwanda Avenue, Haven Avenue, and Archibald Avenue.

Much of the historical information on US 66 in Pasadena, Los Angeles, and Santa Monica was sourced from Jim Powell of the Route 66 Association in Missouri, as well as updates from the Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January and September 2022; Jim Ross on FB, September 2022:

Pasadena

In June 2017, there was an article on an unusual concrete highway marker on former US 66, at Colorado and Holliston Streets in Pasadena. The marker is a 3-foot tall concrete tablet that looks like a tombstone. On the face of the concrete tablet is the number 11 with a circle around it, the numbers 220 and 200, and the letters “F” and “B.” The marker is the only remant of a county house addressing system proposed by Albert Bancroft. Implementation of the system included concrete milestones, which identified the name of the road and the distance from the county courthouse, which was the starting point for the numbering system. By 1908, work was completed on six major thoroughfares, including Foothill Boulevard. So the number 11 with a circle around it tells us that we are 11 miles from the old county courthouse – today the site of the Foltz Criminal Court Building in downtown L.A. The “F” and the “B?” They tell us that we are on the old Foothill Boulevard Route. And the 220 and 200 tell us the block numbers.
(Source: Hidden History of LA, 6/8/2017)

As noted, the original routing of U.S. 66 through Pasadena was part of LRN 9, which was defined in 1909 as one of the very early state highways in California resulting from the first State Highway Bond Act, for $18,000,000, issued in 1909 to establish a State Highway system. See below for the discussion of the original terminus in San Fernando.

Prior to 1933, routing and signage in the cities was up to the Auto Club of Southern California. The earliest ACSC records show the alignment of US 66 traveling westward from Pasadena on the following route until 1929:
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

The routing of LRN 9 (US 66) through Pasadena was: right on Shamrock Ave. in Monrovia, left on Foothill Blvd. through Arcadia into Pasadena, left on Santa Anita Ave. right on Colorado Street and left on Fair Oaks Ave.

In 1929 there was a shift of the alignment of US 101 in downtown Los Angeles off of 2nd Street at Figueroa Street.  US 101 was routed southwest on Figueroa Street to 7th Street, US 101 subsequently took 7th Street over the Los Angeles River.  This move to 7th Street shifted US 66 southward to a new terminus on Broadway at 7th Street. 
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

In December of 1930, the City of Los Angeles (working with the City of Santa Monica to extend US 66 to the coast) selected a route through L.A. that began at their boundary with Pasadena on Colorado Blvd. then to Eagle Rock Blvd. and from there to Fletcher Ave., Glendale Blvd., Rowena Ave., Hyperion Ave., Fountain Ave., and Myra Ave. to Santa Monica Blvd. and then on to Santa Monica. Markers went up in January 1931, but without approval of the state highway department or AASHO, and apparently without the consent of Pasadena officials, who had already selected Ave. 64 in their city for US 66 leading to Los Angeles. Not surprisingly, the unauthorized markers were ordered removed by the state engineer only four months later from what has become known as the “rogue” route.
(Source: Jim Ross on FB, 9/27/2022)

California researcher Ian Bowen has done an exhaustive study on the possible Eagle Rock/Fletcher alignment. Included in his findings are documents suggesting that the US 66 terminus subsequent to the rogue route debacle became US 101 (Sunset Blvd.) via Eagle Rock/Fletcher, and remained so until 1935. According to a letter from the state engineer in April 1931, removing the signs from the City of Santa Monica back to US 101 (Sunset) would fulfill AASHO’s route definition that the terminus be in Los Angeles. It is not known if this was acted upon or approved, and another document from November 1931 identifies the terminus as Fletcher and San Fernando Rd. Supporting both possibilities is a photo of a US 66 marker at Fletcher and San Fernando Rd. dated 1932, although it is possible there was an error in the photo’s date or that the sign was related to the temporary construction route along Eagle Rock during the same timeframe. Regardless of which scenario one may favor, what is conspicuously missing are highway maps from 1931-1935 depicting the Eagle Rock/Fletcher route as mainline US 66.
(Source: Jim Ross on FB, 9/27/2022)

Before the construction of the Pasadena Freeway, US 66 ran S along Figueroa (LRN 165, defined in 1933) to US 101 (LRN 2). Once the freeway was completed, the prior routing was resigned as Alternate US 66, and US 66 was resigned to run S on Fair Oak to pick up the freeway, and then S on the Pasadena Freeway (Route 11, cosigned in portions with US 6, LRN 205, defined in 1935) to US 101. Note: Until 1935, the western terminus of US 66 was on Broadway Street in downtown Los Angeles at 7th Street which carried US 101 at the time. The very early state maintained alignment of US 66 and US 101 can be seen on the 1935 California Division of Highways map of Los Angles County. In October 1935, CHPW reported that US 66 had been extended from Sunset Blvd in Los Angeles to Santa Monica via Santa Monica Blvd. Note that there were a variety of end-points for US 66 during the 1930s.
(Sources: Various, Gribblenation Route 66)

The ACSC signed alignment of US 66 shifted in 1931 and was reportedly in use until some point in 1934.  The 1931 alignment of US 66 from Pasadena westward to Los Angeles was as follows:
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

There were attempts to reroute this highway from this original routing, due to a job in Arcadia. In a letter dated January 29, 1932, from Wm. Dunkerley, Secretary and Manager of the Pasadena Chamber of Commerce & Civic Association, to W.C. Markham, Executive Secretary of AASHTO, there is the statement: We have made request upon the State Highway Engineer at Sacramento for a rerouting of US 66 into Pasadena from Arcadia in order that a road jog in this highway might be avoided.

Markham replied on February 4, 1932, as follows: I have your letter of January 29th, in reference to re-routing U.S. 66 into Pasadena from Arcadia. I do not know what reference is made by the State Highway Engineer of your State in reference to a ruling we have made that would not permit your request being approved. Your letter gives so little information that I am not able to judge what the controversy is.

On March 9, 1932, Dunkerley responded to Markham as follows: Replying to your most recent inquiry, what we are most interested in is to provide the most convenient and easily accessible route into and through Pasadena. The enclosed map, while but a sketch, will explain what we have in mind. The route in red indicates the present routing of U. S. 66 into and through Pasadena [The routing shown as north on Santa Anita in Arcadia, west on Foothill Blvd, south on Santa Anita in Pasadena and west on Colorado Street]; the blue indicates what we consider the most practical and convenient. [This route was straight through on Huntington Drive into Colorado Street.] We would like to know whether or not this can be accomplished. The State Highway Engineer has advised us that it is not within his power owing to a rule of your Association.

On March 15, 1932, Markham wrote the following to Dunkerley: I wish to acknowledge receipt of your letter of March 9th, in reference to your proposed rerouting of U.S. 66 through the City of Pasadena. I wish to say that as far as the routing of a U.S. Number through a city is concerned that is a detail to be worked out entirely by the State Highway Department of the State involved.

On August 21, 1933, pursuant to a letter and resolution dated August 16, 1933, the California Legislature, in accordance with Section 363r of the Political Code, Chapter 326, approved LRN 161 in Los Angeles County. LRN 161 was 17 miles in length, and described as: "State Highway Route 4 [LRN 4] near Glendale to State Highway Route 9 [LRN 9] near Monrovia. This connection carries from the San Fernando Road northwest approach to Los Angeles due easterly to the Foothill Boulevard, passing through and serving large communities on direct routing. The western terminus is on Southern Pacific shipping and passenger point, and at a point correlated with continuous routings to the Ventura Boulevard and to Santa Monica that will facilitate such movement. The route affects intercounty traffic as well as local.". This says the highway is from San Fernando Road (US 99) in Glendale to Shamrock Ave. in Monrovia along Colorado Blvd./Street into Huntington Drive. This road was signed as Route 134, and the parallel portion of LRN 9 on Foothill Blvd. was signed as Route 118. Colorado Street in Pasadena was also dual signed as US 66 at this time.

Additional information on all the various routings and reroutings of US 66 in Pasadena into Downtown Los Angeles are detailed in the Gibblenation Blog The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles. There were at least three alignments of US 66 between Colorado Blvd and US 101 before the Arroyo Seco Parkway came into play. The Gribblenation Blog gives the specifics. These included routings along Eagle Rock Blvd and Temporary LRN 165 on Avenue 64 and York Blvd,
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

After 1933, the state could maintain routes in the city, leading to the creation of LRN 165. Much of the early US Route system around Los Angeles was heavily altered at this point.  Sometime between late 1934/early 1935 the route of US 101 was realigned through downtown Los Angeles via Sunset Boulevard and Macy Street.  This in turn truncated US 66 from 7th Street to US 101 at Sunset Boulevard.  During 1934, US 99 was realigned off a multiplex of US 66 from Pasadena-San Bernardino (LRN 9) to a new alignment which took it to Redlands via downtown Los Angeles, Pomona and Colton (LRN 26).
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

By 1935 the process was started to extend US 66 to US 101A in Santa Monica via what was Route 2.  This became official in January 1936. Another change happened in July 1936 when the fourth Figueroa Street Tunnel opened to traffic. This changed where US 66 met US 101. US 66 now continued through the tunnel to meet US 101 downtown. By 1938, US 6 (extended to California in 1937) multiplexed US 99/LRN 4 on San Fernando Road, where the two routes joined US 66/Route 11/LRN 165 through the Figueroa Street Tunnels.  By 1943, US 66 was shifted onto the Arroyo Seco Parkway entirely whereas Route 11 joined it with US 6/US 99 via San Fernando Road. 
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

At the eastern edge of Pasadena, US 66 ran along Colorado Blvd (LRN 161), with the I-210 Freeway routing along LRN 240. Scott Parker at AAroads noted that there was an Alternate US 66 along Colorado Blvd. west of Fair Oaks Ave (LRN 9 turned north and NW along Sign Route 118) west to Figueroa St., where Alternate US 66 (along with Sign Route 11, which joined Alt. US 66 from Linda Vista Ave. south of the Rose Bowl) turned south (the whole of Sign Route 11 was LRN 165). LRN 161 continued west through Glendale and Burbank, signed as Route 134, originally terminating at US 101/LRN 2 in Sherman Oaks but cut back to Lankershim Blvd. (LRN 159) in North Hollywood circa 1957. The purpose of the 2nd section of LRN 161 was simply to straighten out the alignment of US 66 in the Pasadena/Arcadia area.

In 1940, US 66 was rerouted onto the new Arroyo Seco Parkway, and the older route on Figueroa Street was co-signed with Route 11 as US 66 Alternate.  This made US 66A the designation across the Colorado Street Bridge west of downtown Pasadena. US 66 was truncated to Needles in 1963, removing the official US 66 designation from Route 11 (although signs likely remained), and getting rid of US 66A. The 1964 renumbering created Route 248 to sign the underlying state highway across Colorado, and US 66 remained signed to Monrovia although the route was Route 248.
(Source: Gribblenation Blog (Tom Fearer), "Former California State Route 248 (Old US Routes 66-99 from Pasadena to Monrovia)", 10/2022)

In 1964, the former US 66 routing along the Colorado Street Bridge, Colorado Boulevard, Colorado Place, and Huntington Boulevard became Route 248, although it was signed as US 66 (Route 248 was a placeholder for the dying US 66). In the Pasadena area, signage of US 66 would be truncated from Pasadena to US 95 when I-40 was completed through the Bristol Mountains in 1972.  At that point, portions of Route 248 became signed as (California) Route 66.
(Source: Gribblenation Blog (Tom Fearer), "Former California State Route 248 (Old US Routes 66-99 from Pasadena to Monrovia)", 10/2022)

In 1986, Chapter 928 truncated Route 248 out of Pasadena: “Route 134 near the east limit of the City of Pasadena to Route 210 near Monrovia.” This left Route 248 as starting just W of Rosemead Blvd, Route 164. Field signage at this time is unknown. In 1992, the remainder of Route 248 was deleted by AB 3090, Chapter 1243.

Arroyo Seco Parkway

On September 7, 1940, Purcell (Dept. of Highways) wrote Markham (AASHTO) as follows:

Pursuant to the Purpose and Policy of the American Association of State Highway Officials in the establishment of US Numbered Highways, we hereby make formal application to change the route of US 66 between Pasadena and Los Angeles, from Colorado and Figueroa Streets to the Arroyo Seco Parkway, and to designate the existing route between these points as US 66 ALTERNATE.

The proposed new route, which is expected to be opened to traffic next New Year's Day, shortens the distance by approximately 2.35 miles, and affords travel a new freeway consisting of a six lane divided highway.

As the motoring public will be better served by using this new thoroughfare, permission is requested to place US 66 ALTERNATE markers on the present routing [From Colorado Street and Broadway In Pasadena, easterly along Colorado Street to Figueroa Street thence southerly along Figueroa Street to the Arroyo Seco Parkway in Los Angeles], and to erect US 66 signs on the Arroyo Seco Parkway."

On October 9, 1940, Markham replied to Purcell as follows:

We have your letter of September 7 in reference to re-routing locally U.S. 66 between Pasadena and Los Angeles.

In view of the fact that the slight change you proposed to make in this routing does not involve any key points in the description, it will not be necessary to file this request with the Committee. It might be well, however, for us to notify the map makers as to when it will go into effect, in case they give a local enlargement of the routing in metropolitan Los Angeles.

San Fernando

LRN 9 was defined in 1909 as one of the very early state highways in California resulting from the first State Highway Bond Act, for $18,000,000, issued in 1909 to establish a State Highway system. It had a routing of "San Fernando to San Bernardino".

It appears that the original intent was to have the highway continue along LRN 9 and terminate in San Fernando, where the route would meet US 99. This is based on a letter dated March 1, 1927, from California State Highway Engineer R.M. Morton replied to AASHO Executive Secretary W.C. Markham conveying it was the understanding of the state that US 66 ended in San Fernando.  The description of US 99 would have it jog south into Los Angeles and then follow a multiplex of US 66 east to San Bernardino.
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

On April 26, 1927, W.C. Markham wrote in a letter to California Highway Commission Office Engineer L.T. Cambell stating it would be preferable to have US 66 end somewhere in Los Angeles.  W.C. Markham noted US 66 was already being promoted as the primary highway in the Chicago-Los Angeles Corridor.  W.C. Markham goes onto suggest that it would be helpful if signage of the western terminus of US 66 was placed in the nearest convenient location within the City of Los Angeles.  The terminus of US 66 in San Fernando is described as a technical error and that the last City on the Route Description should be Los Angeles.
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

By 1928, US 66 was stated in the January 1928 California Highways & Public Works as terminating in Los Angeles via San Fernando. This implied that US 66 was to be signed somewhere via multiplex of US 99 on San Fernando Road into the City Limits of Los Angeles.  However prior to 1933, the Division of Highways was not actively involved in maintaining urban highways outside of occasional cooperative projects, and the responsibility for signage of US Routes in cities was given to the Automobile Club of Southern California (ACSC) in the Southern California region. They were free to sign as they please, adding to the confusion.
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

According to the California Historic Route 66 Association pre-1932 ACSC records indicate that the routing of early US 66 was concurrent with that of the National Old Trails Road (NOTR) between Pasadena and Los Angeles. In April of 1912 the NOTR was organized with the goal of signing a trans-continental highway between Baltimore and Los Angeles. For this discussion, the relevant portion is the portion between San Bernardino and Los Angeles. From San Bernardino beginning at Mount Vernon Avenue/4th Street the NOTR followed existing LRN 9 westbound to Pasadena.  Upon reaching Pasadena the NOTR branched away from LRN 9.  The NOTR westbound jogged south on Santa Anita Avenue to Colorado Boulevard in Pasadena and departed towards Los Angeles via Fair Oaks Avenue.  The NOTR followed Fair Oaks Avenue, Huntington Drive and Broadway into downtown Los Angeles where it terminated at the intersection of 7th Street and Broadway. This is the origin of the 7th Street and Broadway terminus for US 66. The initial draft of the US Route System approved by the Secretary of Agriculture in November 1925 showed planned US 60 (later renumbered as US 66) as following the NOTR from the Arizona State Line to a terminus in Los Angeles. 
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", September 2022)

Los Angeles / Santa Monica Terminus

ACSC originally signed US 66 to terminate at Broadway and US 101 at 2nd Street in downtown Los Angeles. This was independent of the Department of Highways, which had the terminus in San Fernando. So even though the DOH though the terminus was San Fernando in 1929, the ACSC seemingly signed it in Los Angeles. By 1931, a shift in the alignment of US 101 changed the ACSC-signed terminus to US 101 at 7th Street.

Even as early as 1931, there was a push by the City of Santa Monica to get the route to terminate in Santa Monica. Santa Monica did about everything it possibly could to get US 66 extended into its boundaries.  These attempts went as far as funding the Auto Club of Southern California to sign US 66 through Los Angeles all the way to Ocean Avenue via Santa Monica Boulevard from December 1930-January 1931. (Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022)

AASHO minutes show a route in flux. An exchange of letters dated to November/December 1931 between C.H. Purcell the California State Highway Engineer and W.C. Markham Executive Secretary of the AASHO indicated that the DOH wanted to split US 66 into a mainline routing terminating at US 101 in downtown Los Angeles and an Alternate Route which bypassed downtown towards US 101 at Sunset Boulevard.   AASHO recommended extending US 66 to Santa Monica so that they Mainline and Alternate Route would have a meet up point via US 101. Ultimately the Division of Highways is shown to not have wanted a US 66 ending in Santa Monica whereas the AASHO didn't want dual terminus points.  But key to these documents is that they show the terminus point for US 66 ending at US 99/San Fernando Road via Fletcher Drive (very different than the ACSC signage).
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

The AASHTO Database file for 1931 also shows a letter dated April 7, 1931 that states that there was rogue signage placed by the ACSC extending US 66 to Santa Monica.  C.H. Purcell states in a response letter that this signage was not officially approved by the AASHO and had been placed by the ACSC at the behest of the City of Los Angeles and Los Angeles County.  Notably the despite the ACSC committing to remove US 66 signage in the Los Angeles-Santa Monica corridor it is not fully clear if they actually ever did.  A photo from Santa Monica Boulevard looking east from Pandora Avenue on January 31, 1935, shows Route 2 shields instead of US 66.  The Sign State Routes had been announced the previous August which included Route 2. City Council minutes from the time (1931) indicate that the ACSC signage of US 66 within the City of Los Angeles began on Colorado Boulevard at the Los Angeles/Pasadena City Lines.  US 66 followed Colorado Boulevard, Eagle Rock Boulevard (formerly Glassell Avenue), and Fletcher Drive to US 99 at San Fernando Road.  US 66 continued westward via Glendale Boulevard, Rowana Boulevard, Hyperion Avenue, Myra Avenue, the viaduct under Sunset Boulevard and Santa Monica Boulevard to the City of Santa Monica.  The signage of US 66 to Santa Monica was requested by the Santa Monica-Ocean Park Chamber of Commerce at their own expense.  The Los Angeles City Council approved the request to extend Santa Monica on December 15, 1930. 
(Source: Gribblenation Blog (Tom Fearer), "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", January 2022)

In an update to his Gribblenation Blog "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles" in February 2022, Tom Fearer summarized the pre-1935 changes to the route in Los Angeles as follows:
(Source: FB introduction to Gribblenation Blog updates; Gribblenation Blog "The Arroyo Seco Parkway and early terminus points of US Route 66 in Los Angeles", February 2022)

Santa Monica

Santa Monica longed pushed to have the western end of US 66 be located in Santa Monica. As early as 1928, Santa Monica was planning to send delegates to the June 6, 1928, US Route 66 Association convention Flagstaff in an attempt to secure the western terminus of the highway. In 1929, it was reported that Los Angeles intended to aid the city of Santa Monica in signing US 66 to their boundaries.  The Los Angeles city engineer John C. Shaw was directed by the Los Angeles City Council to cooperate with extending US 66 to Santa Monica.  US 66 is noted in the article to be currently signed to the western terminus at the Los Angeles/Pasadena city limit at the western edge of the Colorado Street Bridge.  A planned routing for US 66 through Los Angeles to Santa Monica is described as following Pasadena Avenue, York Boulevard, Eagle Rock Boulevard, Fletcher Drive, Glendale Boulevard, Rowena Avenue, Hyperion Avenue, Fountain Avenue, and Myra Avenue.  No planned terminus for US 66 in Santa Monica was cited.
(Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022)

As of 1930, US Routes were not yet signed within Los Angeles.  The Los Angeles City Council voted to have the ACSC sign US 99 and US 101 during the February 5th, 1930, meeting but not US 66.  The rationale by the Los Angeles City Council for not having the ACSC sign US 66 was due to the uncertainty of the location of the highway.  In 1930 the City of Santa Monica petitioned the Los Angeles City Council to have the ACSC sign US 66 through Los Angeles to their city limit at their expense.  The Los Angeles City Council approved the request to allow the ACSC to sign US 66 to Santa Monica on December 15, 1930.  The Los Angeles City Council notably did not petition the California Highway Commission or AASHO regarding the signing of US 66 to Santa Monica.  The ACSC signage began on Colorado Boulevard at the Los Angeles/Pasadena City Lines.  US 66 followed Colorado Boulevard, Eagle Rock Boulevard (formerly Glassell Avenue), and Fletcher Drive to US 99 at San Fernando Road.   US 66 continued westward via Glendale Boulevard, Rowana Boulevard, Hyperion Avenue, Myra Avenue, the viaduct under Sunset Boulevard, and Santa Monica Boulevard to the city of Santa Monica.
(Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022)

The AASHTO Database file for 1931 shows a letter dated April 7th that illustrates the California Highway Commission and AASHO had become aware of US 66 being signed through Los Angeles to Santa Monica.  California State Highway Engineer C.H. Purcell acknowledges in a response letter to the AASHO Executive Secretary that the US 66 signage in Santa Monica was not officially approved by the AASHO and had been placed by the ACSC at the behest of the City of Los Angeles and Los Angeles County.  C.H. Purcell notes the ACSC had agreed to withdraw US 66 signage from the city limit of Santa Monica.  No officially established western terminus of US 66 is discussed in the exchange of letters. The signage was removed at the end of May 1931.
(Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022)

In an exchange of letters at the end of 1931 between C.H. Purcell (the California State Highway Engineer) and W.C. Markham (Executive Secretary of AASHO),  Markham conveys a desire to split US 66 into a mainline routing terminating at US 101 in downtown Los Angeles at Sunset Boulevard via Broadway and an Alternate Route which bypassed downtown towards US 101 at Sunset Boulevard via Hyperion Avenue.   AASHO recommended extending US 66 to Santa Monica so that the Mainline and Alternate Route would have a meet-up point via US 101. But this notion didn't fly.
(Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022)

On June 14th, 1935, the California State Highway Engineer submitted a request to extend US 66 from the intersection of Broadway and Sunset Boulevard in Los Angeles to the intersection of Lincoln Boulevard and Pennsylvania Avenue in Santa Monica. 
(Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022)

On June 17, 1935, the AASHTO minutes simply state that: "US 66 was extended from Los Angeles to Santa Monica." The effective date of the change was January 1, 1936. As for the end in Santa Monica: on June 14, 1935, Purcell wrote Markham as follows: There are attached eighteen copies of detailed description with sketches showing proposed routing of Extension of US Highway No. 66 from Los Angeles to Santa Monica. Annoucement of the extension was to be delayed until the extension of US 6 to long beach was completed.

This extension as shown in description is recommended for approval.

Here's the description, as submitted:

PROPOSED EXTENSION OF US 66 DISTRICT 711 TO SANTA MONICA

Beginning at the intersection of North Broadway and Sunset Boulevard, the junction of US 66, US 99, and US 101, in the City of Los Angeles; thence, northwesterly over Sunset Boulevard (State Highway Route 2) and US 101 to Santa Monica Boulevard; thence, westerly over Santa Monica Boulevard (a city street) to Myra Avenue, the junction of State Highway 162 [LRN 162] and Sign Route (2) [Route 2]; thence, continuing westerly over Santa Monica Boulevard (State Highway Route 162 [LRN 162]) and Sign Route (2) [Route 2] through the Cities of Los Angeles and Beverly Hills to the intersection of Santa Monica Boulevard and Lincoln Boulevard, in the City of Santa Monica; thence, southerly along Lincoln Boulevard to the terminus at Pennsylvania Avenue, a total distance of approximately 13.00 miles.

Remember, in 1935, Olympic Boulevard had been approved as LRN 173, but had not been constructed. This road was later marked as Route 26. If, however one was to draw a line from Pennsylvania Ave. to the junction of LRN 162 (Route 2 and US 66) with LRN 60 (Route 1 and US 101A) at Lincoln Blvd., the points would match. The highway department obviously used Pennsylvania Ave. as the point of reference since Olympic Blvd. did not yet exist.

U.S. 66 end at U.S. 101AIn the announcement of the formal extension of US 66 in the July 2, 1935, Santa Monica Outlook, the article notes US 66 was to be extended back to Ocean Avenue via Santa Monica Boulevard to an interim terminus.  The article notes the change of Sign Route 3 on Roosevelt Highway to US 101A as being critical in making the extension of US 66 to Santa Monica official.  The interim terminus of US 66 via LRN 162 to Ocean Avenue in Santa Monica was necessary due to the incomplete new tunnel alignment (McClure Tunnel) that carry US 101A/LRN 60 through Palisades Bluff.  The extension of US 66 to Santa Monica truncated Route 2 to Hyperion Avenue along LRN 162.  The opening of the Santa Monica Tunnel (McClure Tunnel) and realignment of US 101A/LRN 60 rendered the interim alignment of US 66 at Ocean Avenue via Santa Monica Boulevard obsolete.  The terminus of US 66 then followed LRN 162 to US 101A/LRN 60 at the intersection of Lincoln Boulevard and Olympic Boulevard.
(Source: Gribblenation Blog (Tom Fearer), "The bizarre history of the western terminus of US Route 66 in Santa Monica", October 2022; Image source: US Ends.Com)

By 1936, US 66 then ran NW on US 101 (LRN 2, defined in 1909) to Santa Monica Blvd. At Santa Monica, US 66 exited and continued W to Santa Monica. In 1936, it terminated at Lincoln and Olympic. There is a plaque at the Palisades Bluffs at Ocean Avenue (LRN 162, defined in 1933) where Santa Monica Blvd meets Ocean commemorationg the end of US 66, the "Will Rogers Highway", "Main Street of the USA", but this is not the official terminus (just near it).

Alternate Routes Alternate Routes

US Rte 66 Alternative ProposalIn February 1956, the States of Nevada, California, and Arizona submitted a request to the AASHO to establish US 66A (Alternate) to Las Vegas.  The proposed US 66A would have originated from mainline US 66 in Kingman Arizona and followed a multiplex of US 93/US 466 to Las Vegas, Nevada.  From Las Vegas, Nevada, the proposed US 66A would have multiplexed US 91/US 466 back to mainline US 66 in Barstow, California.  The request to establish US 66A was denied during June 1956 due to it being completely multiplexed with other US Routes.
(Source: Gribblenation Blog (Tom Fearer), "Paper Highways: Proposed US Route 66 Alternate to Las Vegas, Nevada", July 2022)

In November 1955, it was reported that during improvements to Cajon Pass, LRN 191 was signed as US 66 Alternate (in reality US 66 Business).  The US 66 Business Loop followed LRN 191 on Kendall Drive and E Street to Highland Avenue.  From Highland Avenue the US 66 Business Loop followed Route 18 via E Street and 5th Street back to mainline US 66 through downtown San Bernardino.  The original US 66 Business Loop in San Bernardino is unique in that it was chosen to follow an alignment which never part of mainline US 66.  A 1951 article noted that the I Street Overhead was to carry Route 18 and US 66 Business via LRN 9 over what had been previous an at-grade crossing of the Atchison, Topeka & Santa Fe Railway (ATSF) mainline through San Bernardino.  Prior to the opening of the I Street Overhead, both Route 18 and US 66 Alternate were aligned on 3rd Street.
(Source: Gribblenation Blog (Tom Fearer), "Former California State Route 206 and the original US Route 66 Business Loop in San Bernardino", July 2022)

The US 66 Alternate routing may go back to the 1940s. The 1942 USGS Map of San Bernardino displays Route 18 and US 66 Alternate on 3rd Street between E Street and Mount Vernon Avenue.  US 66 Alternate would have connected with mainline US 66 at 4th Street via Mount Vernon Avenue. It appears this signage of the alternate routing was done either by the Division of Highways or by San Bernardino; it was not approved by AASHO.
(Source: Gribblenation Blog (Tom Fearer), "Former California State Route 206 and the original US Route 66 Business Loop in San Bernardino", July 2022)

Business Routes Business Routes

There were two Business US 66 alignments that were approved: one on the Figueroa Street alignment in Los Angeles and a second following what became Route 206 in San Bernardino.

See the ALTERNATE discussion above for the original business loop in San Bernardino, which may have been signed as "Alternate". In terms of formal requests, the Division of Highways submitted a request on May 13, 1958, to create a new US 66-US 91-US 395 Business Loop in San Bernardino due to the construction of I-15.  The new US 66 Business Loop followed Mount Vernon Avenue and 5th Street in San Bernardino via the original surface routing of the highway.  The request by the Division of Highways also sought to eliminate the existing US 66 Business Loop on LRN 191, Kendall Drive, E Street and 5th Street.  The AASHO approved the Division of Highways request on June 26, 1958, which eliminated the US 66 Business Loop on LRN 191
(Source: Gribblenation Blog (Tom Fearer), "Former California State Route 206 and the original US Route 66 Business Loop in San Bernardino", July 2022)

Historical Route Historical Route

Unsigned The portion of the current Route 66 (CA 66) in Los Angeles County is unsigned. With respect to the former US 66 routing, some cities are now using using the "Historic US 66" signage. Monrovia is an exception; they are using an old-style cut-out U.S. highway shield (i.e., the shield that includes the state name). In Glendora, they have renamed Alosta Avenue as Route 66.

This route is part of "Historic Highway Route 66", designated by Assembly Concurrent Resolution 6, Chapter 52, in 1991.

Status Status

In October 2016, the CTC authorized relinquishment of right of way in the city of San Bernardino along Route 215 from 2nd Street to 16th Street and on Route 66 (“H” Street) from 4th Street to 6th Street (08-SBd-215-PM 6.8/7.6, and 08-SBd-66-PM S23.16/S23.41), consisting of superseded highway and collateral facilities. The City, by freeway agreement dated January 21, 2003, agreed to accept title upon relinquishment by the State. The 90-day notice period expired August 29, 2016.

US Highway Shield In April 2016, it was reported that Barstow, with the help from a committee made up of community stakeholders, is working on a Downtown/Route 66 Specific Plan. The city hired a company called MIG to help develop the plan, which is supposed to set a vision for growth and revitalization along the city's historic Route 66 business corridor and within the downtown business and cultural district. The plan includes goals, policies, action strategies, development standards and design guidelines with the goal of drawing more visitors to Barstow's segment of Route 66. The plan addresses a lot of appearance issues and suggests adding more color to the area. Signs and lighting are also addressed. The draft plan, however, also involves investment by the city and California. Directional and landmark signs play a major role. There are five proposed locations for directional signs to downtown Barstow. There are three sign locations along I-15 to notify motorists of upcoming off-ramps to the Barstow Factory Outlets and downtown, a directional sign located on Route 58 prior to the Main Street exit and one directional sign location on I-40 to alert motorists of the Main Street exit. The city is also getting ready to install eight automobile-themed signs down the Route 66 corridor. He said each one will have certain classic cars on them. The draft plan also suggests bringing back the neon signs to increase visibility for businesses. The businesses are also encouraged to incorporate art into signage.
(Source: Victorville Daily Press, 4/23/2016; Route66 News, 5/4/2016)

US Highway Shield There may be a risk to the section of former US 66 near Amboy, due to potential expansion of the Marine Corps base in the 29 Palms area. In August of 2008, the U.S. Marine Corps filed with the Bureau of Land Management for the withdrawal of 422,000 acres contiguous with the Twentynine Palms base in San Bernardino County. These lands were being considered for a possible base expansion, and are a mixture of private property, wildlife reserves, BLM lands and State recreation areas. The proposal for the eastern expansion would extend northward to the southern edge of the National Trails/Route 66 highway, on the alignment loop south of I-40, just east of Bagdad and Amboy. The expansion, if executed, would remove the entirety of Amboy Crater from public access. More information from the neighbors in the area can be found at the Desert Neighbors Site. Later reports indicate that the current EIS seems to have abandoned expansion to the north in favor of expansion to the west and a small piece to the south.

US Highway Shield In March 2017, it was reported that San Bernardino County Public Works will be constructing two new bridges and road improvements on National Trails Highway (Former US 66) at Dola Ditch (2.08 miles east of Kelbaker Road) and Lanzit Ditch (2.77 miles east of Kelbaker Road), east of the community of Amboy. The construction will include removing the existing timber bridges and constructing new timber bridges. A portion of National Trails Highway will be closed at all times to through traffic, including emergency vehicles. Traffic will be routed around the construction on public streets and highways. The detour plan includes using I-40 and Kelbaker Road. Local residents and businesses will have access from Essex Road west to the construction site, but there will be no traffic through the construction site. Construction of the project is tentatively scheduled to start in March 2017 and run through mid-September 2017. The release noted the replacement of two bridges is part of a long-term plan to replace 127 bridges along the Former US 66 corridor in the Mojave Desert. Many of the bridges are 80 to 90 years old and are deemed functionally obsolete and structurally deficient. This is the second extended closure of Former US 66 in the Mojave in recent years. Flash flooding in September 2014 damaged dozens of bridges and the roadway itself, forcing San Bernardino to close Former US 66 for months. It took six months for the county to reopen just the 28-mile part of the road from Ludlow to Amboy. To this day, a part of National Trails Highway from Exit 115 of I-40 to just east of Essex remains closed because of the damage. Most Former US 66 travelers, however, go to Essex through Goffs Road and the roadside town of Fenner.
(Source: Route 66 News, 3/2/2017)

National Trails National Trails

Arrowhead Trail Sign This route (both present-day Route 66 and as historic US 66) was part of the "Arrowhead Trail (Ocean to Ocean Trail)". It was named by Resolution Chapter 369 in 1925.

National Old Trails Road Sign This route (both present-day Route 66 and as historic US 66) was part of the "National Old Trails Road".

Santa Fe Trail Sign This route (both present-day Route 66 and as historic US 66) was part of the "Santa Fe Trail".

National Park to Park Highway Sign Pikes Peak Ocean to Ocean Highway Sign This route (both present-day Route 66 and as historic US 66) appears to have been part of the "National Park to Park Highway", and the "Pikes Peak Ocean to Ocean Highway".

Other WWW Links Other WWW Links

Statistics Statistics

Overall statistics for Route 66:

Pre-1964 Legislative Route Pre-1964 Legislative Route

The route that would become LRN 66 was first defined in 1921 by Chapter 845, which called for the transfer and conveyance to the state of “... that certain road situated in the county of San Joaquin ... to wit: Beginning at a point on the W boundary of the city of Manteca, and on the township line between T1S and T2S, R7E, Mt Diablo base and meridian, and running thence W on the township line to the W side of the Southern Pacific RR RoW to the state highway at the Mossdale School...” In 1933, the route was extended from [LRN 4] near Manteca to [LRN 13] near Oakdale. In 1935, it was captured into the state highway code as:

  1. [LRN 5] near Mossdale School to [LRN 4] at Manteca
  2. [LRN 4] near Manteca to [LRN 13] near Oakdale

In 1961, Chapter 1146 combined the segments and changed the western end to Route 238 near Mossdale, making the definition "[LRN 238] near Mossdale to [LRN 13] near Oakdale via the vicinity of Manteca."

LRN 238 was the routing for the eventual freeway I-5 (Westside Alignment), and LRN 66 started a few miles E of Tracy (near the present I-205/I-5 junction). Before LRN 238 was defined, this route started at LRN 5, which was US 50. The route (LRN 66) ran to LRN 13, which was Route 108 (unsigned in 1934). LRN 66 was signed as Route 120 from the start of state signage in 1934.


Acronyms and Explanations:


Back Arrow Route 65 Forward Arrow Route 67

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