Millersylvania Park is pretty easy to find and a nice straight shot up I-5 for about 99% of the way.
Also, on an in-game note, you may want to reach out to some of the characters in town on the IG board to figure out where you're going to stay. Sleeping isn't assigned "per group" as I know it is in some chapters on the East Coast, so you'll want to find some people to stay with (or risk it on your own, which is certainly doable but not quite as safe). Or, if your character knows any characters from this chapter, or knows characters in *other* chapters that know characters in this chapter, you might try to get an 'in' to a "safe" cabin that way. The cabins are heated and pretty well situated, although you can of course bring a tent for yourself if so inclined.
-Bryan