There are
2,607 mi
from Gaithersburg, MD to Rosemead, CA
That's the driving distance. It would take 1 day 22 hours to go from Gaithersburg, Maryland to Rosemead, California.
The flight distance (direct flight from Gaithersburg, MD to Rosemead, CA) is 2,274.22 mi.
2,607 mi = 4,195.66 kms