There are
654 mi
from Clarksville, TN to Garland, TX
That's the driving distance. It would take 11 hours 49 mins to go from Clarksville, Tennessee to Garland, Texas.
The flight distance (direct flight from Clarksville, TN to Garland, TX) is 582.88 mi.
654 mi = 1,051.74 kms