There are
1,682 mi
from Great Falls, MT to Lyndon, KY
That's the driving distance. It would take 1 day 6 hours to go from Great Falls, Montana to Lyndon, Kentucky.
The flight distance (direct flight from Great Falls, MT to Lyndon, KY) is 1,440.34 mi.
1,682 mi = 2,707.57 kms