There are
2,570 mi
from Buena Park, CA to Hagerstown, MD
That's the driving distance. It would take 1 day 21 hours to go from Buena Park, California to Hagerstown, Maryland.
The flight distance (direct flight from Buena Park, CA to Hagerstown, MD) is 2,245.94 mi.
2,570 mi = 4,135.76 kms