There are
2,898 mi
from Vacaville, CA to Danbury, CT
That's the driving distance. It would take 2 days 2 hours to go from Vacaville, California to Danbury, Connecticut.
The flight distance (direct flight from Vacaville, CA to Danbury, CT) is 2,548.34 mi.
2,898 mi = 3.22 kms