US 70's insane extension to California

[sparker]

AZ didn't mind multiplexes, but it certainly didn't care much for useless duplications to an arbitrary terminus (which is why US 93 was never extended into metro Phoenix)

I don't know if you're aware, but in 1979 AZDOT actually requested an extension of US 93 to Phoenix.  AASHTO denied it, and for some reason AZ never tried again.

I did not know that.  Question:  was that action about the same time that US 89 was decommissioned south of I-40?  If so, then maybe there was pressure at the time to ensure that at least one N-S US highway entered Phoenix.  I'm also guessing that in the ensuing years outsized growth in the region served as its own self-generating expansion mechanism; the extension of a US highway wasn't, in later years, considered a necessary component of that growth, so further pursuit of such an extension simply wasn't taken. 

[US 89]

AZ didn't mind multiplexes, but it certainly didn't care much for useless duplications to an arbitrary terminus (which is why US 93 was never extended into metro Phoenix)

I don't know if you're aware, but in 1979 AZDOT actually requested an extension of US 93 to Phoenix.  AASHTO denied it, and for some reason AZ never tried again.

I did not know that.  Question:  was that action about the same time that US 89 was decommissioned south of I-40?  If so, then maybe there was pressure at the time to ensure that at least one N-S US highway entered Phoenix.  I'm also guessing that in the ensuing years outsized growth in the region served as its own self-generating expansion mechanism; the extension of a US highway wasn't, in later years, considered a necessary component of that growth, so further pursuit of such an extension simply wasn't taken.

89 was decommissioned south of Flagstaff in 1992. In my opinion it should have stayed at least to Wickenburg.

As for Phoenix, wasn't the 60/70/80/89 multiplex in downtown once also concurrent with AZ 93?

[Max Rockatansky]

AZ didn't mind multiplexes, but it certainly didn't care much for useless duplications to an arbitrary terminus (which is why US 93 was never extended into metro Phoenix)

I don't know if you're aware, but in 1979 AZDOT actually requested an extension of US 93 to Phoenix.  AASHTO denied it, and for some reason AZ never tried again.

I did not know that.  Question:  was that action about the same time that US 89 was decommissioned south of I-40?  If so, then maybe there was pressure at the time to ensure that at least one N-S US highway entered Phoenix.  I'm also guessing that in the ensuing years outsized growth in the region served as its own self-generating expansion mechanism; the extension of a US highway wasn't, in later years, considered a necessary component of that growth, so further pursuit of such an extension simply wasn't taken.

89 was decommissioned south of Flagstaff in 1992. In my opinion it should have stayed at least to Wickenburg.

As for Phoenix, wasn't the 60/70/80/89 multiplex in downtown once also concurrent with AZ 93?

It was:

https://www.arizonaroads.com/maps/1961-5.jpg

And yes, US 89 ought to still be around...preferably on AZ 89A. 

[sparker]

AZ didn't mind multiplexes, but it certainly didn't care much for useless duplications to an arbitrary terminus (which is why US 93 was never extended into metro Phoenix)

I don't know if you're aware, but in 1979 AZDOT actually requested an extension of US 93 to Phoenix.  AASHTO denied it, and for some reason AZ never tried again.

I did not know that.  Question:  was that action about the same time that US 89 was decommissioned south of I-40?  If so, then maybe there was pressure at the time to ensure that at least one N-S US highway entered Phoenix.  I'm also guessing that in the ensuing years outsized growth in the region served as its own self-generating expansion mechanism; the extension of a US highway wasn't, in later years, considered a necessary component of that growth, so further pursuit of such an extension simply wasn't taken.

89 was decommissioned south of Flagstaff in 1992. In my opinion it should have stayed at least to Wickenburg.

As for Phoenix, wasn't the 60/70/80/89 multiplex in downtown once also concurrent with AZ 93?

It was:

https://www.arizonaroads.com/maps/1961-5.jpg

And yes, US 89 ought to still be around...preferably on AZ 89A. 

Wholly concur -- but at the same time, ADOT should re-designate AZ 89 from the 89A junction north to I-40 as a northern extension of AZ 69 (at least until NAU students start stealing the 69 shields). 

[Max Rockatansky]

AZ didn't mind multiplexes, but it certainly didn't care much for useless duplications to an arbitrary terminus (which is why US 93 was never extended into metro Phoenix)

I don't know if you're aware, but in 1979 AZDOT actually requested an extension of US 93 to Phoenix.  AASHTO denied it, and for some reason AZ never tried again.

I did not know that.  Question:  was that action about the same time that US 89 was decommissioned south of I-40?  If so, then maybe there was pressure at the time to ensure that at least one N-S US highway entered Phoenix.  I'm also guessing that in the ensuing years outsized growth in the region served as its own self-generating expansion mechanism; the extension of a US highway wasn't, in later years, considered a necessary component of that growth, so further pursuit of such an extension simply wasn't taken.

89 was decommissioned south of Flagstaff in 1992. In my opinion it should have stayed at least to Wickenburg.

As for Phoenix, wasn't the 60/70/80/89 multiplex in downtown once also concurrent with AZ 93?

It was:

https://www.arizonaroads.com/maps/1961-5.jpg

And yes, US 89 ought to still be around...preferably on AZ 89A. 

Wholly concur -- but at the same time, ADOT should re-designate AZ 89 from the 89A junction north to I-40 as a northern extension of AZ 69 (at least until NAU students start stealing the 69 shields).

I never really understood what the purpose of having US 89 through Ash Fork was once AZ 79 was finished through Oak Creek Canyon in the late 1930s.  The Ash Fork corridor was supposed to be part of US 280 but was last minute swapped to an extension of US 89.  It's clear that Arizona wanted US 89 to go through Jerome which is understandable given how important it's mines were in the early 20th century.  I've heard people say nowadays that Oak Creek Canyon, Mingus Mountain, and Yarnell Hill aren't worth of a US Route...total crap IMO.  There is still things like US 191 over the Coronado Trail and US 550 over the Million Dollar Highway that are equally as haggard...as well as scenic.  It's a real shame that cities like Sedona, Cottonwood, and Prescott are no longer part of a larger national network. 

Personally I would align AZ 69 over Fain Road and the Pioneer Parkway to current AZ 89.  The west Pioneer Parkway and the current surface highway to downtown Prescott could be assigned X69 numbers. 

[US 89]

I never really understood what the purpose of having US 89 through Ash Fork was once AZ 79 was finished through Oak Creek Canyon in the late 1930s.  The Ash Fork corridor was supposed to be part of US 280 but was last minute swapped to an extension of US 89.  It’s clear that Arizona wanted US 89 to go through Jerome which is understandable given how important it’s mines were in the early 20th century.  I’ve heard people say nowadays that Oak Creek Canyon, Mingus Mountain, and Yarnell Hill aren’t worth of a US Route...total crap IMO.  There is still things like US 191 over the Coronado Trail and US 550 over the Million Dollar Highway that are equally as haggard...as well as scenic.  It’s a real shame that cities like Sedona, Cottonwood, and Prescott are no longer part of a larger national network. 

SR 89A is a great scenic route, but it's nowhere near the best, fastest through route. If Google is right, you save over 30 minutes on the Flagstaff-Prescott drive if you go through Ash Fork compared to going through Sedona and Cottonwood. 89A also has several sections near Jerome that really aren't all that conducive to long distance truck traffic.

I realize there are other US routes with extremely mountainous sections like US 550, but in that case there's no other road between Durango and Ridgway that doesn't involve a long detour out to Cortez, and 550 is by far the fastest route from Durango to places like Montrose or Grand Junction. In places where there isn't much in the way of Interstate service, US highways generally follow the best inter-city connecting routes. Don't get me wrong, 89A is an awesome road - but it's silly to pretend it's the best Prescott-Flagstaff route, especially when there are obvious quicker alternatives. In the event of a US 89 re-extension I wouldn't mind making 89A an ALT or even SCENIC bannered route, but I just don't think it's a good choice for a mainline US highway.

[sparker]

^^^^^^^^^^^
I always thought that the ideal extension for US 89 would be the Lake Mary road segueing onto AZ 87 down into metro Phoenix.  But present 89A would work as well -- provided ADOT erected signage at the ends suggesting that it might not be the optimal choice for trucks (such as the L-shaped AZ 89/I-40 "detour" via Ash Fork), similar to CA's big yellow signs to that effect.  There's plenty of places across the country where the more efficient and higher capacity route isn't necessarily a US highway (e.g. the paired US 222 and PA 272 in SE PA). 

But getting back to the subject of the OP and the possibility of using what's now CA 74 as a US 70 alignment -- IMO -- and just for the section from San Juan Capistrano to Lake Elsinore alone (I used to drive that at least once every few weeks eastbound to get home from Irvine corporate meetings that invariably ran late, and avoiding CA 91 through Santa Ana Canyon like the plague!).  If you get used to it, it's not horrible, but certainly not an appropriate artery for heavy truck traffic.  The section over the San Jacintos is quite similar to CA 33 from Ojai to CA 166; a lot of switchbacks and curvature -- but that was good enough for old US 399 back in the day!  More of a PITA because of the overall length of the bothersome segment rather than its severity;  while the scenery is fine, the driving experience gets tiring! 

[Max Rockatansky]

That's why I draw the comparison to stuff like the Old Ridge Route and Jack Rabbit Trail.  The Pines to Palms segment of CA 74 was far more in line with what one light expect on US 399 on the Maricopa Highway or to some extent Ridge Route Alternate.  The Ortega Highway seems to be a sticking point for a lot of people but by the standard of the 1930s it isn't too far off what one would expect for a US Route.  Lest we forget US 466 had a pretty haggard dirt segment west of Creston in the 1930s and Tehachapi-Woodford Road was no joke either. 

Regarding AZ 89A it is the preferred route coupled with AZ 260 to get freight to Sedona and Cottonwood.  AZ 179 is not truck friendly at all with all the roundabouts which leads most truckers to 89A.  AZ 89 north of Prescott is a far more gentle grade but is surprisingly light on traffic.  Either way both corridors have merit and probably shouldn't have been punted to State Route status to begin with. 

[sparker]

That's why I draw the comparison to stuff like the Old Ridge Route and Jack Rabbit Trail.  The Pines to Palms segment of CA 74 was far more in line with what one light expect on US 399 on the Maricopa Highway or to some extent Ridge Route Alternate.  The Ortega Highway seems to be a sticking point for a lot of people but by the standard of the 1930s it isn't too far off what one would expect for a US Route.  Lest we forget US 466 had a pretty haggard dirt segment west of Creston in the 1930s and Tehachapi-Woodford Road was no joke either. 

Regarding AZ 89A it is the preferred route coupled with AZ 260 to get freight to Sedona and Cottonwood.  AZ 179 is not truck friendly at all with all the roundabouts which leads most truckers to 89A.  AZ 89 north of Prescott is a far more gentle grade but is surprisingly light on traffic.  Either way both corridors have merit and probably shouldn't have been punted to State Route status to begin with. 

Interestingly, before I-17 was planned over the (original) AZ 69/79 composite corridor (where it is now), it was to follow US 89 from Wickenburg to Ash Fork -- the obvious "path of least resistance" in the mid-50's.  AZ 89, and US 89 before it, was a very fast road; considering the growth of the Prescott area both before and after the US decommissioning in the early '90's, the decision to truncate the US route is questionable at best and, at worst, a gratuitous and unnecessary arbitrary decision -- likely done to remove the multiplex of US 89 over I-40 (which in reality was probably never a navigation issue any more in 1992 than it was previously). 

IMO, a practical solution (other than the Lake Mary approach I previously iterated) involving keeping a US route through Prescott would be to restore US 89 to AZ 89; keeping 89A a state highway poses no particular issues.  Seeing that the use of the US 60 loop through Wickenburg is only situationally useful (problems on I-10 west of Buckeye), 60 could be removed west of Tempe, with west of Wickenburg replaced by a AZ 74 western extension.  The Grand Avenue/Wickenburg "diagonal" could be co-signed as US 89 & US 93, both terminating at I-17 in Phoenix (ADOT would just have to suck it up regarding "useless" multiplexes, as both designations denote useful egresses northward from the metro area).   Now that probably won't happen; the record for restoring US highways previously decommissioned isn't exactly stellar regarding any state.  But IMO it'd be quite appropriate!     

[Max Rockatansky]

Straying into fictional territory but adding to the point above.  Some of the newer corridors in Arizona are far superior than what was available in the heyday of the US Route System.  Personally I found that AZ 260 and AZ 87 was a far superior route between Mesa-Show Low over US 60 through Globe.  Would it not be viable to realign US 60 into Phoenix via 202, 260, and 87 then extend US 70 to to I-10 in Tempe?  That would leave the corridor of Wickenburg to I-17 open for either US 89 or US 93 (although I prefer the former due to I-11) and an 89A could be rerouted wherever.  AZ 77 would be fine as a stand alone through Salt River Canyon and AZ 74 would be fine extended again westward to I-10.  That would put two X0 US Routes ending in a major city. 

Regarding AZ 260 I would cut it back to Show Low-Eagar (better yet reactive US 260 in place of US 180 and reactivate AZ 279 in Verde Valley.  AZ 87 south of Mesa is functionally being slowly decommissioned anyways so it probably could just have it's signage removed or assigned an AZ X87 that is available.  All these moves would certainly clear up multiplexes and utilize the best newer mountain corridors to full effect in Arizona. 

But then again that's just all a pipe dream assuming there would be the will to change up the highway designations nowadays. 

[Konza]

Or you could multiplex US 60 and US 70 on the Superstition Freeway from Country Club west to I-10 and let the routes terminate together.

[Konza]

After a drive up to Show Low yesterday, I'd like to double down on my opinion on this one.  The Salt River Canyon is spectacular, but if there is an alternative to it being on an x0 US route, it should be pursued. 

ADOT has overhead message boards in Show Low with driving times to Phoenix via both Us 60 and AZ 260/87.   They're within minutes of each other.  Most of the AZ 87/260 route is already four lanes.  It's a better route, and should have the more prominent route number.

I was coming from south of Tucson, so I probably would have not driven through the Phoenix area yesterday regardless of how the routes were marked, but I would have been more than OK with the road through Globe and the Salt River Canyon being just AZ 77.

[Max Rockatansky]

After a drive up to Show Low yesterday, I'd like to double down on my opinion on this one.  The Salt River Canyon is spectacular, but if there is an alternative to it being on an x0 US route, it should be pursued. 

ADOT has overhead message boards in Show Low with driving times to Phoenix via both Us 60 and AZ 260/87.   They're within minutes of each other.  Most of the AZ 87/260 route is already four lanes.  It's a better route, and should have the more prominent route number.

I was coming from south of Tucson, so I probably would have not driven through the Phoenix area yesterday regardless of how the routes were marked, but I would have been more than a OK with the road through a Globe and the Salt River Canyon being just AZ 77.

The corridor improvements on 87/260 have been massive these past three decades and long surpassed Salt River Canyon.  I recall driving 87/260 when they were mostly two lane highways.  As the 2010s wore on 87/260 became my favored route for my weekly work trip up to the Show Low Area over US 60.  If it wasn't for the mines in Globe I doubt many truckers would bother with US 60 through Salt River Canyon anymore.   

[sparker]

After a drive up to Show Low yesterday, I'd like to double down on my opinion on this one.  The Salt River Canyon is spectacular, but if there is an alternative to it being on an x0 US route, it should be pursued. 

ADOT has overhead message boards in Show Low with driving times to Phoenix via both Us 60 and AZ 260/87.   They're within minutes of each other.  Most of the AZ 87/260 route is already four lanes.  It's a better route, and should have the more prominent route number.

I was coming from south of Tucson, so I probably would have not driven through the Phoenix area yesterday regardless of how the routes were marked, but I would have been more than a OK with the road through a Globe and the Salt River Canyon being just AZ 77.

The corridor improvements on 87/260 have been massive these past three decades and long surpassed Salt River Canyon.  I recall driving 87/260 when they were mostly two lane highways.  As the 2010s wore on 87/260 became my favored route for my weekly work trip up to the Show Low Area over US 60.  If it wasn't for the mines in Globe I doubt many truckers would bother with US 60 through Salt River Canyon anymore.   

Pre-extensive Interstate deployment (circa early '59) my dad and his brother made a cross-country trip to visit my grandfather, who was having serious medical issues, and they used US 60 east to Clovis, NM, and US 70 east from there to their destination of Broken Bow, OK.  That was my dad's first trip through the Salt River Canyon; on return (they thought better of it and came back via US 80 and US 70 via Safford) he couldn't stop talking about how dangerous that road was and how it should be avoided whenever possible.  He described it as all switchbacks and horseshoe curves getting down to the bottom of the canyon and the same getting up the other side.  But then he hated curvy 2-lane roads in general; he readily condemned the original SSR 198 over the Coast Range from San Lucas to Coalinga as "going around every fucking tree they could find!" -- although now I can attest to that highway's improvement in the meantime; it's quite an enjoyable drive.   

[Max Rockatansky]

After a drive up to Show Low yesterday, I'd like to double down on my opinion on this one.  The Salt River Canyon is spectacular, but if there is an alternative to it being on an x0 US route, it should be pursued. 

ADOT has overhead message boards in Show Low with driving times to Phoenix via both Us 60 and AZ 260/87.   They're within minutes of each other.  Most of the AZ 87/260 route is already four lanes.  It's a better route, and should have the more prominent route number.

I was coming from south of Tucson, so I probably would have not driven through the Phoenix area yesterday regardless of how the routes were marked, but I would have been more than a OK with the road through a Globe and the Salt River Canyon being just AZ 77.

The corridor improvements on 87/260 have been massive these past three decades and long surpassed Salt River Canyon.  I recall driving 87/260 when they were mostly two lane highways.  As the 2010s wore on 87/260 became my favored route for my weekly work trip up to the Show Low Area over US 60.  If it wasn't for the mines in Globe I doubt many truckers would bother with US 60 through Salt River Canyon anymore.   

Pre-extensive Interstate deployment (circa early '59) my dad and his brother made a cross-country trip to visit my grandfather, who was having serious medical issues, and they used US 60 east to Clovis, NM, and US 70 east from there to their destination of Broken Bow, OK.  That was my dad's first trip through the Salt River Canyon; on return (they thought better of it and came back via US 80 and US 70 via Safford) he couldn't stop talking about how dangerous that road was and how it should be avoided whenever possible.  He described it as all switchbacks and horseshoe curves getting down to the bottom of the canyon and the same getting up the other side.  But then he hated curvy 2-lane roads in general; he readily condemned the original SSR 198 over the Coast Range from San Lucas to Coalinga as "going around every fucking tree they could find!" -- although now I can attest to that highway's improvement in the meantime; it's quite an enjoyable drive.   

A guy I worked with back in the early 2010s was absolutely terrified of Salt River Canyon. He had a huge fear of heights and had to lay down I the back of the work truck if he went with me to Show Low or TorC via US 60.  Personally I never found Salt River Canyon all that bad so long as you didn't get stuck behind a truck.  The hairpins are wide enough to allow pullouts and I never thought the grades were steep enough to require lower gears. 

Now the Old Mustang Grade of CA 198, man that looks like that was a beast.  I found a CHPW article from 1944 when that thing was replaced with the modern highway.  I've found both endpoints of the Old Mustang Grade, unfortunately one was fenced off and overgrown much like Old CA 25 on Lewis Creek Road. 

[sparker]

^^^^^^^^^^^
Looks like my dad missed the 198 upgrades by a couple of years.  He worked (management) at the original Lockheed "skunk works" in Burbank during WWII, and had to personally deliver some "packages" to Camp Roberts north of Paso Robles back in '42 (he had no idea what was in them -- as he said, classified well above his pay grade!).  But he had some time off after the delivery, so he decided to visit his uncle over in Dinuba -- hence the trip over 198 that resulted in his dismal opinion of the facility!  In retrospect, he should have gone down to 41 and then over that way into the Valley -- but he also hated to backtrack, so 198 it was! 

[Max Rockatansky]

^^^^^^^^^^^
Looks like my dad missed the 198 upgrades by a couple of years.  He worked (management) at the original Lockheed "skunk works" in Burbank during WWII, and had to personally deliver some "packages" to Camp Roberts north of Paso Robles back in '42 (he had no idea what was in them -- as he said, classified well above his pay grade!).  But he had some time off after the delivery, so he decided to visit his uncle over in Dinuba -- hence the trip over 198 that resulted in his dismal opinion of the facility!  In retrospect, he should have gone down to 41 and then over that way into the Valley -- but he also hated to backtrack, so 198 it was!

Yeah the difference between the old grade and modern grade is massive.  Much of the original alignment of 198 in Warthan Canyon was gradually straightened after that point.  There was a bunch of floating bridges on early 198 in Warthan Canyon that were designed to detach so they could be salvaged after floods.  I would imagine the Parkfield Grade is probably a decent analog as to how Warthan Canyon once was on 198. 

[ftballfan]

After a drive up to Show Low yesterday, I'd like to double down on my opinion on this one.  The Salt River Canyon is spectacular, but if there is an alternative to it being on an x0 US route, it should be pursued. 

ADOT has overhead message boards in Show Low with driving times to Phoenix via both Us 60 and AZ 260/87.   They're within minutes of each other.  Most of the AZ 87/260 route is already four lanes.  It's a better route, and should have the more prominent route number.

I was coming from south of Tucson, so I probably would have not driven through the Phoenix area yesterday regardless of how the routes were marked, but I would have been more than a OK with the road through a Globe and the Salt River Canyon being just AZ 77.

The corridor improvements on 87/260 have been massive these past three decades and long surpassed Salt River Canyon.  I recall driving 87/260 when they were mostly two lane highways.  As the 2010s wore on 87/260 became my favored route for my weekly work trip up to the Show Low Area over US 60.  If it wasn't for the mines in Globe I doubt many truckers would bother with US 60 through Salt River Canyon anymore.   

Pre-extensive Interstate deployment (circa early '59) my dad and his brother made a cross-country trip to visit my grandfather, who was having serious medical issues, and they used US 60 east to Clovis, NM, and US 70 east from there to their destination of Broken Bow, OK.  That was my dad's first trip through the Salt River Canyon; on return (they thought better of it and came back via US 80 and US 70 via Safford) he couldn't stop talking about how dangerous that road was and how it should be avoided whenever possible.  He described it as all switchbacks and horseshoe curves getting down to the bottom of the canyon and the same getting up the other side.  But then he hated curvy 2-lane roads in general; he readily condemned the original SSR 198 over the Coast Range from San Lucas to Coalinga as "going around every fucking tree they could find!" -- although now I can attest to that highway's improvement in the meantime; it's quite an enjoyable drive.   

A guy I worked with back in the early 2010s was absolutely terrified of Salt River Canyon. He had a huge fear of heights and had to lay down I the back of the work truck if he went with me to Show Low or TorC via US 60.  Personally I never found Salt River Canyon all that bad so long as you didn't get stuck behind a truck.  The hairpins are wide enough to allow pullouts and I never thought the grades were steep enough to require lower gears. 

Now the Old Mustang Grade of CA 198, man that looks like that was a beast.  I found a CHPW article from 1944 when that thing was replaced with the modern highway.  I've found both endpoints of the Old Mustang Grade, unfortunately one was fenced off and overgrown much like Old CA 25 on Lewis Creek Road. 

Current CA 198 doesn't look bad at all. Did the Old Mustang Grade deviate significantly from the current route?

[Max Rockatansky]

After a drive up to Show Low yesterday, I'd like to double down on my opinion on this one.  The Salt River Canyon is spectacular, but if there is an alternative to it being on an x0 US route, it should be pursued. 

ADOT has overhead message boards in Show Low with driving times to Phoenix via both Us 60 and AZ 260/87.   They're within minutes of each other.  Most of the AZ 87/260 route is already four lanes.  It's a better route, and should have the more prominent route number.

I was coming from south of Tucson, so I probably would have not driven through the Phoenix area yesterday regardless of how the routes were marked, but I would have been more than a OK with the road through a Globe and the Salt River Canyon being just AZ 77.

The corridor improvements on 87/260 have been massive these past three decades and long surpassed Salt River Canyon.  I recall driving 87/260 when they were mostly two lane highways.  As the 2010s wore on 87/260 became my favored route for my weekly work trip up to the Show Low Area over US 60.  If it wasn't for the mines in Globe I doubt many truckers would bother with US 60 through Salt River Canyon anymore.   

Pre-extensive Interstate deployment (circa early '59) my dad and his brother made a cross-country trip to visit my grandfather, who was having serious medical issues, and they used US 60 east to Clovis, NM, and US 70 east from there to their destination of Broken Bow, OK.  That was my dad's first trip through the Salt River Canyon; on return (they thought better of it and came back via US 80 and US 70 via Safford) he couldn't stop talking about how dangerous that road was and how it should be avoided whenever possible.  He described it as all switchbacks and horseshoe curves getting down to the bottom of the canyon and the same getting up the other side.  But then he hated curvy 2-lane roads in general; he readily condemned the original SSR 198 over the Coast Range from San Lucas to Coalinga as "going around every fucking tree they could find!" -- although now I can attest to that highway's improvement in the meantime; it's quite an enjoyable drive.   

A guy I worked with back in the early 2010s was absolutely terrified of Salt River Canyon. He had a huge fear of heights and had to lay down I the back of the work truck if he went with me to Show Low or TorC via US 60.  Personally I never found Salt River Canyon all that bad so long as you didn't get stuck behind a truck.  The hairpins are wide enough to allow pullouts and I never thought the grades were steep enough to require lower gears. 

Now the Old Mustang Grade of CA 198, man that looks like that was a beast.  I found a CHPW article from 1944 when that thing was replaced with the modern highway.  I've found both endpoints of the Old Mustang Grade, unfortunately one was fenced off and overgrown much like Old CA 25 on Lewis Creek Road. 

Current CA 198 doesn't look bad at all. Did the Old Mustang Grade deviate significantly from the current route?

It diverged to the south near the schoolhouse in Priest Valley and emerged at Peach Tree Valley Road near Cow Creek.  The road is still there behind gates and can be found on Google Maps. 

But you're right about modern 198, it's a fantastic drive.  In fact Motortrend features it somewhat frequently during their best driver's car test. 

[Duke87]

But the planners of the day chose a much easier path for US 20, across upstate NY, paralleling the old Erie Canal.  And seeing as how US 30 always went through Philadelphia, it was much easier to essentially ignore direct western routes out of NYC, since commerce in that metro area was always destined to thrive even without that type of egress. 

It does seem odd, though, that both US 30 and US 40 end up in Atlantic City. US 30 could have still gone to Philadelphia, then continued to New York (probably riding along with US 1) and ended on Long Island.

It's worth noting that this is exactly what the Lincoln Highway did - went east to Philadelphia, than northeast to NYC.

Indeed, you can trace the the history of these corridors back through other older modes of transportation. The Lincoln Highway followed the same general corridor west from NYC that the Pennsylvania Railroad did. Meanwhile going north up the Hudson and then west across Upstate as the NYS Thruway now does was the routing of the NY Central Railroad and, before that, the routing of the Erie Canal.

Prior to the construction of I-80, there was no direct route from NYC to the midwest (note how it doesn't really parallel any US highways through PA). Trips west used primarily one of the two routes above.

[sparker]

But the planners of the day chose a much easier path for US 20, across upstate NY, paralleling the old Erie Canal.  And seeing as how US 30 always went through Philadelphia, it was much easier to essentially ignore direct western routes out of NYC, since commerce in that metro area was always destined to thrive even without that type of egress. 

It does seem odd, though, that both US 30 and US 40 end up in Atlantic City. US 30 could have still gone to Philadelphia, then continued to New York (probably riding along with US 1) and ended on Long Island.

It's worth noting that this is exactly what the Lincoln Highway did - went east to Philadelphia, than northeast to NYC.

Indeed, you can trace the the history of these corridors back through other older modes of transportation. The Lincoln Highway followed the same general corridor west from NYC that the Pennsylvania Railroad did. Meanwhile going north up the Hudson and then west across Upstate as the NYS Thruway now does was the routing of the NY Central Railroad and, before that, the routing of the Erie Canal.

Prior to the construction of I-80, there was no direct route from NYC to the midwest (note how it doesn't really parallel any US highways through PA). Trips west used primarily one of the two routes above.

The only through NYC (metro; it terminated at the docks in Jersey City) to Chicago railroad that took a relatively direct path west was the Erie; it slithered through the southern Catskills to the Delaware River, used that northwest (and still one of the reasons why NY17/I-86 expansion through Hale Eddy is problematic) and then over the mountains to Binghamton.  From there it pretty much traced NY 17 and/or I-86 over to Jamestown, cut down into northern Ohio, and then struck out (via Lima, OH and Huntington, IN) to Chicago.  Never a major player, it nevertheless found a place when heavy and/or oversized equipment needed hauling because it featured an extra-wide ROW and required high clearances for overcrossings.  Perfect for the old Westinghouse plant in Elmira, NY as well as the various purveyors of construction equipment concentrated around Akron, OH.  An early Jay Gould property, sold to pay off his other debts (and various fines!); it always teetered on insolvency, even with later mergers, until absorbed by Conrail in 1976.  One thing it was known for was having one of the largest locomotives around (primarily for their anthracite coal traffic east of Binghamton) -- the "triplex" 2-8-8-8-2 simple-articulated steam locomotive, with the rear set of drivers under the tender!  Traction up the wazoo, but a maintenance nightmare!   

But the Erie's decidedly limited success illuminates the fact that even early on, the most viable western egress from NYC was either north (to Albany) then west, or southwest (to Philadelphia) then more or less west (much more convoluted than the upstate NY/New York Central pathway).  A simple way to illustrate this is to get a 1958 map and look at where the turnpikes are located. 

[hobsini2]

Just imagine what the multiplex of 1, 9, and 30 would be called... 1930? And if 22 were put on the route of 139 and the surface portion of 78, then it could possibly be 1-9-22-30, which would just be, pardon mon français, a clusterfuck.

Yeah, I suppose four US routes running together would be a bit of a mouthful.

Well, look at all that traffic! That's what happens when route concurrency is allowed to run rampant :-)

Or the multiplex of 12-14-18-151 on the Beltline. https://www.google.com/maps/@43.0373377,-89.3895835,3a,75y,247.95h,79.06t/data=!3m6!1e1!3m4!1swxnqzeNQr0916j1MwCvSsA!2e0!7i16384!8i8192?hl=en

[CNGL-Leudimin]

I've been pondering about US 70, and they could have done differently in 1947, when US 91 was extended to Long Beach. They could have rerouted US 70 instead to give it some sense, and kept US 91 ending in Barstow. Or, if they were making US x1s routes to be as much border-to-border (or to Gulf of Mexico further East) as possible, they could have extended US 91 to San Diego instead, replacing US 395 (this could have been done as early as 1934). If they had done it that way, then in the 1964 "purge" (as I like to call that year's renumbering) they could have truncated US 395 (which would have ended at Victorville like currently does) to Bishop instead of US 6. But that is going into fictional territory.

[sparker]

I've been pondering about US 70, and they could have done differently in 1947, when US 91 was extended to Long Beach. They could have rerouted US 70 instead to give it some sense, and kept US 91 ending in Barstow. Or, if they were making US x1s routes to be as much border-to-border (or to Gulf of Mexico further East) as possible, they could have extended US 91 to San Diego instead, replacing US 395 (this could have been done as early as 1934). If they had done it that way, then in the 1964 "purge" (as I like to call that year's renumbering) they could have truncated US 395 (which would have ended at Victorville like currently does) to Bishop instead of US 6. But that is going into fictional territory.

It's likely that the extension of US 91 back in 1947 was specifically to extend it to somewhere in the L.A. metro area, in keeping with its role as a diagonal route south of central Utah.  But when US 395 was commissioned pre-war, it was definitely as a N-S corridor connecting inland points -- but terminating (south) at a port city -- more or less as an "inland access corridor" serving previously "virgin" territory as far as a through corridor was concerned.  Remember that before the 1950's San Diego was principally a Navy town and minor recreational area; its 1950 incorporated population was under 150K -- hardly considered a major destination -- curiously, the cities near the endpoints of historic US 80 (S.D., Savannah) were similar population until San Diego experienced its outsized "growth spurt" starting in the '50's.  It was probably considered an appropriate terminal point for a 3dus, whereas metro L.A., due to its relatively large presence, was considered to "deserve" an additional 2dus to add to its already impressive mix.  Also, the trajectories of each route essentially placed each at or near where they ended up prior to '64.   

[bugo]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?