There are
722 mi
from Clarksville, TN to Tonawanda, NY
That's the driving distance. It would take 14 hours 2 mins to go from Clarksville, Tennessee to Tonawanda, New York.
The flight distance (direct flight from Clarksville, TN to Tonawanda, NY) is 633.99 mi.
722 mi = 1,162.20 kms