There are
817 mi
from Pasadena, TX to Gallatin, TN
That's the driving distance. It would take 14 hours 53 mins to go from Pasadena, Texas to Gallatin, Tennessee.
The flight distance (direct flight from Pasadena, TX to Gallatin, TN) is 686.21 mi.
817 mi = 1,314.38 kms