There are
2,600 mi
from Gaithersburg, MD to Monrovia, CA
That's the driving distance. It would take 1 day 22 hours to go from Gaithersburg, Maryland to Monrovia, California.
The flight distance (direct flight from Gaithersburg, MD to Monrovia, CA) is 2,268.86 mi.
2,600 mi = 4,183.95 kms