CA 18

[Max Rockatansky]

Figured it was time to open up a thread for CA 18.  I recently drove the expressway portion of CA 18 from San Bernardino north to CA 138 on a segment of the Rim of the World Highway.  CA 18 between between San Bernardino and CA 138 in my opinion is the coolest four-lane expressway in California which tons of turns and huge vistas.  What I really find interesting is that the route of the Rim of the World Highway has origins even before the Holcomb Valley Gold Rush as a logging road that was built in 1852.

https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html

[sparker]

Figured it was time to open up a thread for CA 18.  I recently drove the expressway portion of CA 18 from San Bernardino north to CA 138 on a segment of the Rim of the World Highway.  CA 18 between between San Bernardino and CA 138 in my opinion is the coolest four-lane expressway in California which tons of turns and huge vistas.  What I really find interesting is that the route of the Rim of the World Highway has origins even before the Holcomb Valley Gold Rush as a logging road that was built in 1852.

https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html

I remember when CA 18's expressway portion was opened in late '70 and early '71; my then-fiancée (later wife #1) was from Lake Arrowhead, so we, as UCR students, did a lot of schlepping up and down the hill on weekends.  The upper portion, near the CA 138 junction, was particularly tricky during construction, since they essentially cut further into the hill on the alignment of the original 2-lane highway at that point -- and through traffic was constantly being shifted back and forth onto different cleared lanes -- with a lot of one-way traffic control.  It got so bad for a while that we just headed up Cajon and backtracked on 138 -- but once it was finished, it really cut time off the drive.  It was one hell of an engineering feat! 

[Max Rockatansky]

Figured it was time to open up a thread for CA 18.  I recently drove the expressway portion of CA 18 from San Bernardino north to CA 138 on a segment of the Rim of the World Highway.  CA 18 between between San Bernardino and CA 138 in my opinion is the coolest four-lane expressway in California which tons of turns and huge vistas.  What I really find interesting is that the route of the Rim of the World Highway has origins even before the Holcomb Valley Gold Rush as a logging road that was built in 1852.

https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html

I remember when CA 18's expressway portion was opened in late '70 and early '71; my then-fiancée (later wife #1) was from Lake Arrowhead, so we, as UCR students, did a lot of schlepping up and down the hill on weekends.  The upper portion, near the CA 138 junction, was particularly tricky during construction, since they essentially cut further into the hill on the alignment of the original 2-lane highway at that point -- and through traffic was constantly being shifted back and forth onto different cleared lanes -- with a lot of one-way traffic control.  It got so bad for a while that we just headed up Cajon and backtracked on 138 -- but once it was finished, it really cut time off the drive.  It was one hell of an engineering feat!

Its a pretty damn fine road and really shows what can be accomplished with a good design.  The only route I can think of that kind of resembles it is CA 168 east of Prather climbing to Shaver Lake.

[SoCal Kid]

That scenery is  . Beautiful mountainous views, plus nice coastal views (on CA 1 and some parts of US 101). Thats what I love of California

[Mark68]

I love that stretch of 18 from Waterman all the way past the Crestline turnoff (where the expressway narrows to the 2-lane road toward Big Bear). I have been on that road numerous times (my late grandmother lived in Lake Arrowhead) and it's always a great drive (even when foggy/snowy).

[nexus73]

The closest kind of expressway to this I have seen is US 189 going through Provo Canyon.  On one side, a river.  On the other side, mountain range.  How UDOT was able to squeeze in this road has to go down as an engineering feat of the first order. 

Here is what is literally cool about driving this section of highway.  Shaded all around with wind blowing on the narrow river creates a natural air conditioning which will take a summer day in the 90's as felt in Provo/Orem and turn it into temps in the mid 70's.  All the trees and the river always made me think I had found a slice of Oregon!

Thank you for another outstanding photo essay Max. 

Rick

[Max Rockatansky]

Recently I drove the entire 114 route of CA 18 from CA 210 in San Bernardino up the Rim-of-the-World Highway in the San Bernardino Mountains to Big Bear Valley and through the Mojave Desert to CA 138 in Llano.  That being the case I went back and heavily updated the previous CA 18 blog on the Rim-of-the-World Highway to include the history of the entirety of the highway along with photos of the entire route.  While the full history of CA 18 and full route photos can be found on the link below the abridged historic summary of the highway is as follows:

-  The precursor to CA 18 from San Bernardino up Waterman Canyon to Big Bear was known as Crest Road which was constructed as a logging route in 1852 by Mormon Pioneers.  Crest Road was gradually improved as mining interest in Holcomb Valley and with water rights in Bear Valley increased over the following decades.
-  In 1917 Legislative Route 43 was adopted from where the pavement in Waterman Canyon ended east towards Bear Valley north of Bear Valley Lake.
-  In 1919 a spur of LRN 43 was extended over Bear Valley Dam east through modern Big Bear Lake and Big Bear City.
-  In 1931 LRN 43 was extended northwest from Bear Valley to US 66 in Victorville, south out of Waterman Canyon to San Bernardino and southwest to New Port Beach.
-  In 1934 LRN 43 was signed as CA 18 between CA 19 in Artesia to US 66 in Victorville.
-  In 1947 US 91 was extended from Barstow to Long Beach.  This extension included a multiplex of CA 18 from San Bernardino towards Artesia.
-  CA 30 appears to have first been signed in 1954 and had an eastern terminus at CA 18 in Running Springs.
-  In 1957 CA 30 was extended east on a multiplex to Bear Valley.  CA 30 ran along the south shore of Bear Valley whereas CA 18 stayed on it's original alignment on the north shore.
-  In 1962 CA 18 had a large truncation from Artestia to San Bernardino where it ended at US 66/91/395.
-  In 1964 CA 18 west legislatively extended west from Victorville to Llano on what was the unbuilt LRN 268.  CA 18 was also shifted to the south shore of Big Bear Lake and CA 38 took over the previous north shore alignment. 
-  In 1965 CA 18 was truncated to CA 30 in San Bernardino whereas the previous stub to US 66/91/395 became CA 259.
-  The western extension of CA 18 from Victorville to Llano was complete by 1967.
-  By 1970 CA 18 between San Bernardino and CA 18 was completed to expressway standards.
-  In 1991 CA 18 was shifted out of Bear Valley Lake Village which created the somewhat unofficial CA 18 Business Loop.

https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html


I have about 450 photos over two albums for CA 18 which can be found below:

CA 18 from CA 210 to CA 138

https://flic.kr/s/aHsmDCxuDJ


CA 18 from CA 138 to CA 138

https://flic.kr/s/aHsmHpNmPe

[sparker]

The western extension of CA 18 from I-15 to CA 138 in L.A. County was, prior to its adoption into the state highway system in late '67, a well-used county facility; my dad used to take it when we visited relatives in Las Vegas; it was much better than schlepping east on I-10 (in the early/mid-'60's, the only freeway extending east out of L.A.) and over Cajon, especially on a Friday evening, which is when we usually made the eastbound trip.  Not coincidentally, bringing that road into the system at that particular time was prompted by Southern Pacific's construction of their Palmdale-Colton "cutoff" line enabling freight traffic to bypass central L.A.   The tracks would have crossed that road at a very sharp angle, generally considered the most dangerous crossing type;  San Bernardino County was reluctant (and short of available funds) to pay for a road overpass, so they petitioned the Division of Highways to adopt the road;  it was close to the unadopted CA 18 extension -- but at the time the Division preferred a new-terrain alignment a bit to the north of that road.  But the county was persistent, so in late 1965 the Division "caved" and agreed to take the road into the system and construct an overpass over the new SP line.  When the bridge was completed in the fall of '67, the adoption was formalized.   But even then signage was sporadic, mostly clustered at I-15 and CA 138 as well as the US 395 "crossroads" in west Victorville;  reassurance shields were, for the most part, absent apart from those junctions. 

[Max Rockatansky]

The western extension of CA 18 from I-15 to CA 138 in L.A. County was, prior to its adoption into the state highway system in late '67, a well-used county facility; my dad used to take it when we visited relatives in Las Vegas; it was much better than schlepping east on I-10 (in the early/mid-'60's, the only freeway extending east out of L.A.) and over Cajon, especially on a Friday evening, which is when we usually made the eastbound trip.  Not coincidentally, bringing that road into the system at that particular time was prompted by Southern Pacific's construction of their Palmdale-Colton "cutoff" line enabling freight traffic to bypass central L.A.   The tracks would have crossed that road at a very sharp angle, generally considered the most dangerous crossing type;  San Bernardino County was reluctant (and short of available funds) to pay for a road overpass, so they petitioned the Division of Highways to adopt the road;  it was close to the unadopted CA 18 extension -- but at the time the Division preferred a new-terrain alignment a bit to the north of that road.  But the county was persistent, so in late 1965 the Division "caved" and agreed to take the road into the system and construct an overpass over the new SP line.  When the bridge was completed in the fall of '67, the adoption was formalized.   But even then signage was sporadic, mostly clustered at I-15 and CA 138 as well as the US 395 "crossroads" in west Victorville;  reassurance shields were, for the most part, absent apart from those junctions.

So essentially the only new part is the rail overpass at the Los Angeles County line?   I've always been suspicious of the nature of that section of 18 due to the dips, really soft shoulders and lack of signage.  There isn't even a reassurance US 395 shield at the actual junction from CA 18 west. 

[sparker]

So essentially the only new part is the rail overpass at the Los Angeles County line?   I've always been suspicious of the nature of that section of 18 due to the dips, really soft shoulders and lack of signage.  There isn't even a reassurance US 395 shield at the actual junction from CA 18 west. 

The lack of any reference to US 395 along CA 18 must be a relatively recent occurrence; when I last was through the intersection in late 2012, there was a single US 395 shield with a "crossing" double-arrow indicator below the shield per direction on CA 18; similar shields for CA 18 were posted on both NB and SB US 395.  All these shields were posted within several feet of the intersection itself (a decidedly "minimalist" approach in keeping with Caltrans' apparent de-emphasis on route signage).  Why they're not there now is a mystery!

[Gulol]

If memory serves, back in the mid 1990s,  the 395 reassurance shields at the CA 18 intersection were CA 395 shields instead of US 395.  One of those "wish I got a picture of that" items ...

[Max Rockatansky]

If memory serves, back in the mid 1990s,  the 395 reassurance shields at the CA 18 intersection were CA 395 shields instead of US 395.  One of those "wish I got a picture of that" items ...

That certainly would have been a worthwhile picture to get.  Fortunately AAroads had one loaded to the shield gallery years ago:



Either way today all we got from CA 18 westbound is a US 395 street blade to indicate that the route is present at all:

IMG_3650 by Max Rockatansky, on Flickr

[sparker]

^^^^^^^^^
CA 18 is certainly wider today than it was nearly 7 years ago when I lived down there; and that dedicated right turn lane wasn't there either.  That probably accounts for the disappearance of the US 395 trailblazer shields -- looks like the widening resulted in the removal of the post where the shield was located.  Guess D8 figures the hanging blade is sufficient to identify the crossing route -- it's a shame how such standards have deteriorated!

[Max Rockatansky]

It's definitely different than I remember it being circa 2011-2013 when I worked in the area.  Adalento essentially was a non-existent collection of modular homes lapping US 395 at the time. 

[sparker]

It's definitely different than I remember it being circa 2011-2013 when I worked in the area.  Adalento essentially was a non-existent collection of modular homes lapping US 395 at the time. 

Much of the pre-2010 housing development in Adelanto was well west of 395 and north of CA 18; 395 itself was just starting to host the town's commercial activity via a series of "strip malls" along the west side of the highway with the largest concentration of such just north of 18.  The "old town" Adelanto was further north near Air Base Parkway; development progressed further and further south as "infill" toward the west side of Victorville.  Ironically, before the 2007 "subprime" housing crash, Adelanto had the greatest concentration of below-$200K housing within 100 miles of L.A. (for a while afterward circa 2010-11 one could buy a Adelanto house at the "bargain" median price of around $135K -- it's gone back up since then, according to friends still living in the area).  But the trade-off required to get those low housing prices was the fact that the tracts were well "out in the desert" a mile or two west of US 395; to get to what amenities were out there at the time required a few miles' drive.  Later and pricier development started filling in the area between the original housing tracts and 395;  the "wedge" between 395 and I-15 had long been dotted with sporadic housing dating from the '60's and '70's, typical of the older housing stock in the region.  That area hosted much of the "modular" housing to which Max refers above; that was a product of property owners attempting to cash in on the earlier housing boom by undercutting the tract home prices (zoning was often more honored in the breach rather than observance those days!).  When I was visiting there at the end of last year, I noticed quite a bit of apartment development within the "wedge", much of it along the east side of 395;  it seems that highway is beginning to serve as a "dividing line" between denser development to the east and "traditional" single-unit dwellings to the west.  And, as noted above, 395 itself is increasingly the site of commercial activity between the still-developing housing areas.   How that will play out if and when it is decided to develop a freeway along 395 has yet TBD; the plans, AFAIK, still call for a parallel facility about a half-mile west of the current alignment and cutting back to the original route a couple of miles north of the 15/395 "split" west of Hesperia in order to use the existing ramps as much as possible. 

[sparker]

Relevant (to a CA 18 discussion) side-note to the demise of the HSR freeway/tollway:  It'll be interesting to see if the CA 18 expressway extension of the HDC alignment east of I-15 bypassing Victorville and Apple Valley survives as an independent project or simply "goes down with the ship", so to speak.  ROW acquisition for that project was being discussed locally as early as 2012, before I left for Northern CA.   One of its salient features was that it passed near the massive Wal-Mart distribution center north of Apple Valley on Dale Evans Parkway, providing direct access to and from southward I-15 (which presently utilizes a series of surface roads); that might help to tip the scales for retention of the bypass as a regional "SIU".

[Max Rockatansky]

Relevant (to a CA 18 discussion) side-note to the demise of the HSR freeway/tollway:  It'll be interesting to see if the CA 18 expressway extension of the HDC alignment east of I-15 bypassing Victorville and Apple Valley survives as an independent project or simply "goes down with the ship", so to speak.  ROW acquisition for that project was being discussed locally as early as 2012, before I left for Northern CA.   One of its salient features was that it passed near the massive Wal-Mart distribution center north of Apple Valley on Dale Evans Parkway, providing direct access to and from southward I-15 (which presently utilizes a series of surface roads); that might help to tip the scales for retention of the bypass as a regional "SIU".

That part along with the bypass of Palmdale is really what should have been built out of the High Desert Corridor.  That said it will be interesting to see if replacing a surface highway with speeds as high as 60 MPH in Apple Valley will really fly.  Downtown Victorville is more of the bottleneck point and would be nice get some cars off of D Street.  Either way it make it way easier to get to Big Bear from the desert. 

[sparker]

Relevant (to a CA 18 discussion) side-note to the demise of the HSR freeway/tollway:  It'll be interesting to see if the CA 18 expressway extension of the HDC alignment east of I-15 bypassing Victorville and Apple Valley survives as an independent project or simply "goes down with the ship", so to speak.  ROW acquisition for that project was being discussed locally as early as 2012, before I left for Northern CA.   One of its salient features was that it passed near the massive Wal-Mart distribution center north of Apple Valley on Dale Evans Parkway, providing direct access to and from southward I-15 (which presently utilizes a series of surface roads); that might help to tip the scales for retention of the bypass as a regional "SIU".

That part along with the bypass of Palmdale is really what should have been built out of the High Desert Corridor.  That said it will be interesting to see if replacing a surface highway with speeds as high as 60 MPH in Apple Valley will really fly.  Downtown Victorville is more of the bottleneck point and would be nice get some cars off of D Street.  Either way it make it way easier to get to Big Bear from the desert. 

CA 18 in Apple Valley is a relatively fast arterial as it stands today -- at least until the Victorville in-town stretch along D Street.  But the topology in that immediate area has always mitigated against a simple bypass of that short segment.  The local sentiment, as expressed by both affected cities and the local press has been geared toward getting through traffic away from CA 18 -- especially since an increasing level of truck traffic has elected to use the 18/247/62 continuum around the north side of the mountains to bypass the ever-increasing congestion in the Redlands/San Bernardino area (particularly if their journey places them there during commute periods!); this was becoming increasingly noticeable about the time I moved north in late '12.  There seemed to be a general consensus that the planned northern "arc" around Apple Valley was a reasonable way to approach the issue -- although most locals would have preferred a full freeway instead of the expressway with at-grade signalized intersections that was actually projected (with an interchange at Dale Evans Blvd., likely a concession to Wal-Mart; the full freeway was to extend west of there to I-15, becoming the east end of the HDC west of there).  Most locals considered CA 18 -- at least west of "old town" Apple Valley (at the Joshua intersection) to be a form of expressway, since for much of its length it featured frontage roads and little private access to the through lanes; replicating that format for the bypass was, in some quarters, seen as not much of an improvement.  Nevertheless, it would have removed a considerable level of longer-distance truck traffic from Apple Valley's CBD, so even the bypass expressway plan received grudging acceptance.  I'd take a guess that that portion of the entire project, if supported by local jurisdictions and planning agencies, may well survive independently.  Curiously, the plans for its extension west to US 395 in Adelanto -- as a CA 18 reroute -- were themselves planned separately from the main HDC tollway (the portion between 395 and 15 was not intended to be tolled); since the HDC project wouldn't have become reality until after 2060 in any case, CA 18 would have multiplexed with US 395 south to its present alignment.  Now -- whether that will survive as another SIU section is also up in the air (it would also serve as a "shunt" for truck traffic to and from northward US 395 toward CA 58 at Kramer, taking quite a bit of that traffic off the suburban US 395 stretch from Hesperia to Adelanto).  We'll just all have to see if those localized segments can be revitalized and/or reinstated.     

[cahwyguy]

As I've noted before, I'm going through posts for information for my pages. I hit upon Tom/Max's chronology, and there's an error:

It states:

-  In 1934 LRN 43 was signed as CA 18 between CA 19 in Artesia to US 66 in Victorville.

with a similar error in his blog at https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html :

By 1934 CA 18 was added to LRN 43 between CA 19 in Artesia north to US 66 in Victorville via D Street.

In 1931, LRN 43 was extended down to Newport Beach, along Santa Ana Canyon and what became SSR 55/Route 55. The portion that ran and carried Route 18 ran not to Artesia/Hermosa Beach (that was LRN 175, which became SSR 14 and later Route 91). The portion that carried Route 18 (and US 91 after 1947) was LRN 178, and ran across Lincoln from SSR 59 to SSR 19, Lakewood Blvd. That remained signed as Route 18 until 1953, at which point the US 91 routing went to SSR 14 to US 101, down US 101 to Lincoln, and back on the SSR 18/LRN 178 routing. Whether SSR 18 was signed between 1953 and 1962 is unclear (it shows on state highway maps but has a discontinuity), but by 1962, everything S of San Bernardino was US 91. Post 1963, the routing on Lincoln W of US 101 became Route 214, and disappeared a few years later.

Note: Yes, the 1934 definition says "Artesia". But that was later amended to Lakewood, and SSR 19 is in Lakewood, not Artesia. Artesia is closer to LRN 170, SSR 35, which became I-605.

[Max Rockatansky]

As I've noted before, I'm going through posts for information for my pages. I hit upon Tom/Max's chronology, and there's an error:

It states:

-  In 1934 LRN 43 was signed as CA 18 between CA 19 in Artesia to US 66 in Victorville.

with a similar error in his blog at https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html :

By 1934 CA 18 was added to LRN 43 between CA 19 in Artesia north to US 66 in Victorville via D Street.

In 1931, LRN 43 was extended down to Newport Beach, along Santa Ana Canyon and what became SSR 55/Route 55. The portion that ran and carried Route 18 ran not to Artesia/Hermosa Beach (that was LRN 175, which became SSR 14 and later Route 91). The portion that carried Route 18 (and US 91 after 1947) was LRN 178, and ran across Lincoln from SSR 59 to SSR 19, Lakewood Blvd. That remained signed as Route 18 until 1953, at which point the US 91 routing went to SSR 14 to US 101, down US 101 to Lincoln, and back on the SSR 18/LRN 178 routing. Whether SSR 18 was signed between 1953 and 1962 is unclear (it shows on state highway maps but has a discontinuity), but by 1962, everything S of San Bernardino was US 91. Post 1963, the routing on Lincoln W of US 101 became Route 214, and disappeared a few years later.

Note: Yes, the 1934 definition says "Artesia". But that was later amended to Lakewood, and SSR 19 is in Lakewood, not Artesia. Artesia is closer to LRN 170, SSR 35, which became I-605.

I'm surprised i missed that one.  The maps from the late 1940s onward show the LRNs on the Los Angeles City Insert.  I'll get that one corrected when I get back to the house to tonight. 

[cahwyguy]

By the way, look at my comment in the thread Why Was Riverside Freeway Renumbered?, as that also relates to Route 18.

[sparker]

As I've noted before, I'm going through posts for information for my pages. I hit upon Tom/Max's chronology, and there's an error:

It states:

-  In 1934 LRN 43 was signed as CA 18 between CA 19 in Artesia to US 66 in Victorville.

with a similar error in his blog at https://www.gribblenation.org/2019/05/california-state-route-18-rim-of-world.html :

By 1934 CA 18 was added to LRN 43 between CA 19 in Artesia north to US 66 in Victorville via D Street.

In 1931, LRN 43 was extended down to Newport Beach, along Santa Ana Canyon and what became SSR 55/Route 55. The portion that ran and carried Route 18 ran not to Artesia/Hermosa Beach (that was LRN 175, which became SSR 14 and later Route 91). The portion that carried Route 18 (and US 91 after 1947) was LRN 178, and ran across Lincoln from SSR 59 to SSR 19, Lakewood Blvd. That remained signed as Route 18 until 1953, at which point the US 91 routing went to SSR 14 to US 101, down US 101 to Lincoln, and back on the SSR 18/LRN 178 routing. Whether SSR 18 was signed between 1953 and 1962 is unclear (it shows on state highway maps but has a discontinuity), but by 1962, everything S of San Bernardino was US 91. Post 1963, the routing on Lincoln W of US 101 became Route 214, and disappeared a few years later.

Note: Yes, the 1934 definition says "Artesia". But that was later amended to Lakewood, and SSR 19 is in Lakewood, not Artesia. Artesia is closer to LRN 170, SSR 35, which became I-605.

If indeed the US 91 routing was transferred to LRN 175/SSR 14 after 1953, its overlap with US 101 would have occurred in Fullerton and Anaheim on the former US 101 over LRN 2; until 1957 Manchester Ave. and the ever-lengthening Santa Ana Freeway were still signed (east of SSR 19/Lakewood Blvd.) as Bypass US 101.  It seems that US 91 was rerouted back onto its previous SSR 18 alignment along LRN 178/Lincoln Ave. through the east part of Anaheim all the way to the LRN 43/SSR 55 junction after the US 101 signage was removed from Harbor Blvd (then Spadra Road) and Los Angeles Street in Fullerton & Anaheim.  Curiously, when LRN 181 was deleted at about the same time (ca. '57),  its northernmost segment along Santa Ana Canyon Road was reassigned to LRN 178 for a couple of years until the LRN 175 expressway was completed (as the first O.C. section of the "Riverside Freeway") between Santa Ana Canyon Road and State College Blvd. (LRN 180), at which time US 91 and SSR 18 were shunted north on State College to the new expressway (signed as US 91 and both SSR 14 and SSR 18).  SSR 18 was removed SW of San Bernardino in 1961, and the Riverside Freeway was completed west to the Santa Ana Freeway (then US 101) the following year.  LRN 178 east of LRN 180 was deleted at that point.  But at the end of 1962 US 91 was again moved to Brookhurst Ave. from Lincoln north to the new freeway; that section of city street received signage in the spring of 1963 although it was never brought into the state system -- just as well, since with the statewide renumbering 9 months later US 91 was deleted south of Barstow, and the Riverside Freeway and Santa Ana Canyon Road became new CA 91.   So between 1953 and 1964 US 91 had four different alignments from the west side of Anaheim to Santa Ana Canyon.   Seems D7, which covered O.C. at that time, was in major surface-street relinquishment mode well before that process infected the agency as a whole.  It makes sense when one considers that the area was growing by leaps and bounds at that time, and the cities would want to redirect through traffic away from their city centers and onto the new freeways as soon as feasible.   

[Max Rockatansky]

By the way, look at my comment in the thread Why Was Riverside Freeway Renumbered?, as that also relates to Route 18.

I just read, I went back to the blog and addressed LRN 178 and the State Maintenance Gap.  I didn't deviate off script too much from CA 18 given US 91/CA 91 would be chasing a whole another rabbit hole I'm not really prepared to go into until I get some actual route photos.  I used to have a stock pile of Riverside Freeway photos which would have been really handy in the CA 18 blog and a CA 91/US 91 entry as well.

[cahwyguy]

If indeed the US 91 routing was transferred to LRN 175/SSR 14 after 1953, its overlap with US 101 would have occurred in Fullerton and Anaheim on the former US 101 over LRN 2; until 1957 Manchester Ave. and the ever-lengthening Santa Ana Freeway were still signed (east of SSR 19/Lakewood Blvd.) as Bypass US 101. 

Nope. In 1953, LRN 178 was truncated to start at Manchester, not LRN 2. This means that US 91 would have been routed down LRN 174 (Byp US 101).

It seems that US 91 was rerouted back onto its previous SSR 18 alignment along LRN 178/Lincoln Ave. through the east part of Anaheim all the way to the LRN 43/SSR 55 junction after the US 101 signage was removed from Harbor Blvd (then Spadra Road) and Los Angeles Street in Fullerton & Anaheim. 

Again, can't be, because the portion of LRN 178 from LRN 43 to Manchester was removed from the state system in 1953. So if it went through East Anaheim on Lincoln, it wasn't on LRN 178.

Curiously, when LRN 181 was deleted at about the same time (ca. '57),  its northernmost segment along Santa Ana Canyon Road was reassigned to LRN 178 for a couple of years until the LRN 175 expressway was completed (as the first O.C. section of the "Riverside Freeway") between Santa Ana Canyon Road and State College Blvd. (LRN 180), at which time US 91 and SSR 18 were shunted north on State College to the new expressway (signed as US 91 and both SSR 14 and SSR 18). 

I originally had some connection with SSR 18 and LRN 181, but there really is no legislative evidence of it. The portion of LRN 178 from LRN 168 near Lakewood along Carson-Lincoln was truncated to Manchester in 1953, and LRN 174 in 1957. LRN 181 ran along Grand and Glassell in that point, and a bit along Orange-Olive. There was no transfer of the legislative route. Look at the state highway code.

SSR 18 was removed SW of San Bernardino in 1961, and the Riverside Freeway was completed west to the Santa Ana Freeway (then US 101) the following year. 

That removal shows on the 1962 State Highway Map. The question is: What happened to SSR 18 in the period between 1953 and 1961, especially the portion that had run along Lincoln from Route 55 to Route 19?

LRN 178 east of LRN 180 was deleted at that point. 

No, because LRN 178 E of LRN 174 had been deleted in 1953, essentially.

But at the end of 1962 US 91 was again moved to Brookhurst Ave. from Lincoln north to the new freeway; that section of city street received signage in the spring of 1963 although it was never brought into the state system -- just as well, since with the statewide renumbering 9 months later US 91 was deleted south of Barstow, and the Riverside Freeway and Santa Ana Canyon Road became new CA 91.

I'm just not seeing the evidence of that. The state highway maps show it on LRN 175, which I believe ran along Orangethorpe at that point. When the freeway routing was constructed, it moved onto the freeway.

Daniel

[sparker]

^^^^^^^^^^
Daniel's accounts of the various convolutions of US 91 in O.C. don't in any way match what was actually signed in the field during that period -- or recorded on street maps.  With my family, I made, as a kid (and budding roadgeek with a map collection -- unfortunately now long gone -- dating from about 1954-55) many trips per month down into O.C. to visit my aunt & uncle in Westminster -- and, after '55, just about as many trips down to Disneyland -- my mom was an animation artist at Disney, and had a free pass for herself and her guests -- which was taken advantage of by friends, family and out-of-town visitors on a regular basis.  So we were down there at least 9-10 times a year at a minimum (and we were there opening day in 1955, when I was 5 1/2 years old!).  With those regular trips, I was able to see the progress of the Santa Ana Freeway as it was extended both southeast from L.A. and northwest from its original O.C. segment in Santa Ana.  When the section through Anaheim was opened in late '57, there was US 91 signage at the Lincoln Avenue exit, accompanied until 1961 by SSR 18 signage (and these were posted on the original Big Black Signs prior to the "greening" of such signage).  But there was never any US 91 signage multiplexed onto the Santa Ana Freeway in any direction.   Correspondingly, the intersection of Lincoln Ave. (LRN 178) and Beach Blvd. (LRN 171/SSR 39) featured both 91 & 18 junction signage, with 18 gone after '61.  But both locations' Lincoln Ave.-based references to US 91 remained intact to at least 1963.  Also, I noticed two things in April of that year on a Disneyland trip -- the "BBS" for the LH Santa Ana Freeway exit to the Riverside Freeway no longer cited SSR 14 but instead US 91 (with the white US shield plastered right over the former 14 shield), and the US 91 sign at Lincoln had been blacked out. 

Also, during that timeframe, the Gousha O.C. street map showed the progression of US 91 alignments as I outlined them earlier.  The first, pre-1958, showed 91/18 proceeding east on Lincoln to Orange-Olive, then north about a mile or so to Santa Ana Canyon Road, which terminated at Orange-Olive (originally part of LRN 181).  In '58 that initial segment of the Riverside Freeway between State College/LRN 180 and LRN 43/SSR 55 opened (with a fanfare illustrated article in CH&PW); at that point 91/18 was "shunted" north on State College Blvd. to meet the west end of the new facility, which was signed for US 91 and both SSR's 14 & 18 (it was part of LRN 175); this was cited as the US 91 alignment through 1960.  In 1961/62, after 18's truncation, the Brookhurst routing was shown on those years' Gousha maps; but in 1963 US 91 was shown as multiplexing north from Lincoln with SSR 39 to US 101 (I-5), ostensibly to access the west end of the Riverside Freeway.  However, I can attest that there was never any field signage to this effect -- likely because, like with the US 6 reroute over Lankershim Blvd. in the San Fernando Valley, the preliminary stages of the renumbering that took effect at the end of that year were in progress, and the Division of Highways simply decided to hold off any temporary measures that would be effectively erased the following year.  As far as continuing the US 91/SSR 18 signage on Lincoln east of Manchester/US 101, that was likely a similar process to that utilized for SSR 39's signage over Hacienda Blvd. in L.A. County -- with state-standard '53-spec "post-bear" larger shields -- a matter of cooperating with local jurisdictions for navigational purposes (please note that at the time D7 covered Orange County in addition to their current L.A./Ventura parvenu).  So regardless of any or all legal definitions, there was definitely field signage of both US 91 and SSR 18 clear across O.C. -- in one form or another -- through '63.  And since pretty much all this was predicated on the development of the Riverside Freeway, which was in its preliminary stages in the early '50's -- D7 figured any anomalies, including signage on non-maintained routes, was going to be very temporary in any case.  In any case, the Lincoln alignment's days were always numbered; its post-renumbering ID as CA 214 (which decidedly did terminate at I-5) only lasted a year, being deleted, along with several other surface connectors, in 1965.  But IMO the policy of playing "fast and loose" with signage such as described here is infinitely preferable -- for purposes of navigation -- to the current spate of relinquishments that leave signed highway segments "hanging" at best!