It's best to use cities or towns to find the most accurate route to drive across two states, so this is the midpoint if you're driving between Shottsville, AL and Parker Junction, CA.
The coordinates of the midpoint between California and Alabama are 35° 11' 39" N / 101° 41' 34" W.
The closest city to the midpoint is Pullman, TX.
Alabama and California don't share a border so this is half the straight line distance from the AL-MS state line to the AZ-CA state line.
The exact halfway point between California and Alabama is at 34° 17' 19" N / 101° 8' 39" W.
The closest city to the midpoint is Gray Mule, TX. You can check the distance from Gray Mule to Alabama and compare it to Gray Mule to California.
How far is California from me?