There are
2,631 mi
from Gaithersburg, MD to Long Beach, CA
That's the driving distance. It would take 1 day 23 hours to go from Gaithersburg, Maryland to Long Beach, California.
The flight distance (direct flight from Gaithersburg, MD to Long Beach, CA) is 2,288.59 mi.
2,631 mi = 4,233.96 kms