There are
1,660 mi
from Clarksville, TN to Idaho Falls, ID
That's the driving distance. It would take 1 day 6 hours to go from Clarksville, Tennessee to Idaho Falls, Idaho.
The flight distance (direct flight from Clarksville, TN to Idaho Falls, ID) is 1,385.25 mi.
1,660 mi = 1.61 kms