There are
1,807 mi
from Hayward, CA to Watertown, SD
That's the driving distance. It would take 1 day 7 hours to go from Hayward, California to Watertown, South Dakota.
The flight distance (direct flight from Hayward, CA to Watertown, SD) is 1,382.29 mi.
1,807 mi = 1.61 kms