There are
2,611 mi
from Fullerton, CA to Rockville, MD
That's the driving distance. It would take 1 day 22 hours to go from Fullerton, California to Rockville, Maryland.
The flight distance (direct flight from Fullerton, CA to Rockville, MD) is 2,274.40 mi.
2,611 mi = 4,202.58 kms