There are
2,325 mi
from Vacaville, CA to Romulus, MI
That's the driving distance. It would take 1 day 16 hours to go from Vacaville, California to Romulus, Michigan.
The flight distance (direct flight from Vacaville, CA to Romulus, MI) is 2,033.82 mi.
2,325 mi = 3.22 kms