There are
1,335 mi
from Harlingen, TX to Seymour, IN
That's the driving distance. It would take 1 day to go from Harlingen, Texas to Seymour, Indiana.
The flight distance (direct flight from Harlingen, TX to Seymour, IN) is 1,116.23 mi.
1,335 mi = 2,147.74 kms