There are
2,791 mi
from Gaithersburg, MD to Tualatin, OR
That's the driving distance. It would take 2 days to go from Gaithersburg, Maryland to Tualatin, Oregon.
The flight distance (direct flight from Gaithersburg, MD to Tualatin, OR) is 2,337.18 mi.
2,791 mi = 4,491.25 kms