There are
1,371 mi
from Gaithersburg, MD to Forest Hill, TX
That's the driving distance. It would take 1 day to go from Gaithersburg, Maryland to Forest Hill, Texas.
The flight distance (direct flight from Gaithersburg, MD to Forest Hill, TX) is 1,205.51 mi.
1,371 mi = 2,206.79 kms