There are
1,827 mi
from Downey, CA to Festus, MO
That's the driving distance. It would take 1 day 8 hours to go from Downey, California to Festus, Missouri.
The flight distance (direct flight from Downey, CA to Festus, MO) is 1,570.69 mi.
1,827 mi = 1.61 kms