There are
2,681 mi
from Gaithersburg, MD to Santee, CA
That's the driving distance. It would take 1 day 23 hours to go from Gaithersburg, Maryland to Santee, California.
The flight distance (direct flight from Gaithersburg, MD to Santee, CA) is 2,247.27 mi.
2,681 mi = 4,314.35 kms