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Fault Line Friday; Weird San Andreas Fault Roads between CA 198/25 and CA 41/46

Back in March I had a look at some of the weird roadways along the San Andreas Fault between the junction of CA 198/41 south to CA 46/41.  Specifically I traveled on; Peach Tree Road, Indian Valley Road, Slacks Canyon Road, Vineyard Canyon Road, and Cholame Road.  I started the day out by driving west on CA 198 to the overlook in the Diablos above Peach Tree Valley.  Peach Tree Valley is the boundary line between the Diablo and Gabilan Ranges which are bisected by the San Andreas Fault.


CA 198 drops sharply westbound out of the Diablos to a junction with CA 25 and Peach Tree Road.



Peach Tree Road has a center stripe and is two lanes for the first couple miles south off of CA 198 but that drops a very narrow single lane very quickly.



There is actually a couple interesting overviews of Slack Canyon that are worth stopping for.


Earlier this year Peach Tree Road was shut down while this new bridge was being put in.  The Google Street Vehicle shows the older bridge which looked to be pretty substantially narrow by comparison.



Peach Tree Road terminates here at the junction of Slacks Canyon Road and Indian Valley Road.  For whatever reason Slacks Canyon Road is been gated off and shows being that way pretty much on every GSV screen shot I looked at.  It looks like the Fault continues via Slacks Canyon Road, maybe that along with the lack of pavement was why it was closed? 



Indian Valley Road continues directly south and begins to rise through the Gabilan Range roughly to about 2,200 feet above sea level.


At the summit Indian Valley begins to drop elevation fast, I would say that this is the only section of any of the roads I traveled that had a "mountain road" feel to it.






Gradually Indian Valley Road levels out at about I want to say 1,400 feet, the descent from here on out was much more gentle.


Approaching Valleton and San Miguel there are increasing signs of residential habitation, by this point I still had not encountered another car.  I encountered seven south from this point to Vineyard Canyon Road.


Some nice bridge work near Big Sandy Road.


At the junction of Indian Valley Road and Hare Canyon Road is a community called Valleton.  Really it isn't really much of anything aside from ranch lands and a couple stray abandoned old homes.  Supposedly there was a post office here from the 1880s to almost 1920s, seems like it more or less a real place at one point.


By the time I hit junction with Hare Canyon Road I had traveled 27 miles south from CA 198.


South of Hare Canyon the roadway on Indian Valley begins to widen and basically it becomes somewhat a normal width.


 Eventually US 101 can be seen right before hitting the San Luis Obispo County Line.



 37 miles in I took an eastward swing on Vineyard Canyon Road.


 Vineyard Canyon Road is substantially wider and what I'd expect out of a modern roadway.


 Surprisingly the summit on Vineyard Canyon is pretty high at about 2,500 feet above sea level.


Approaching Slack Canyon Road and the San Andreas Fault there is some more interesting bridge work, I'm not sure what is up with the brown street blades.



The last five miles south to Parkfield-Coalinga Road and Cholame Road are pretty bland, I did make a stop in Parkfield for breakfast.


I did the rest of the Parkfield Grade from CA 198 in 2016, it is actually a pretty cool road.  The creek below is the actual fault line and there is a bow in the bridge that is obvious from outside the car.  I believe Parkfield has been around since the 1850s, there are less than 20 residents supposedly left in the town.  Parkfield is mostly known for being the most seismically active place in the Continental United States.







CA 46/41 is 17 miles of Parkfield via Cholame Road.


Cholame Road has some pretty nice single lane bridges and wide views before terminating at CA 41/46.






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