There are
1,953 mi
from Sunnyvale, CA to Harlingen, TX
That's the driving distance. It would take 1 day 10 hours to go from Sunnyvale, California to Harlingen, Texas.
The flight distance (direct flight from Sunnyvale, CA to Harlingen, TX) is 1,617.91 mi.
1,953 mi = 1.61 kms