There are
2,050 mi
from Gresham, OR to Dekalb, IL
That's the driving distance. It would take 1 day 11 hours to go from Gresham, Oregon to Dekalb, Illinois.
The flight distance (direct flight from Gresham, OR to Dekalb, IL) is 1,687.31 mi.
2,050 mi = 3,298.76 kms