There are
2,100 mi
from Elgin, IL to Rohnert Park, CA
That's the driving distance. It would take 1 day 12 hours to go from Elgin, Illinois to Rohnert Park, California.
The flight distance (direct flight from Elgin, IL to Rohnert Park, CA) is 1,822.16 mi.
2,100 mi = 3.22 kms