There are
2,115 mi
from San Marcos, CA to Frankfort, IN
That's the driving distance. It would take 1 day 13 hours to go from San Marcos, California to Frankfort, Indiana.
The flight distance (direct flight from San Marcos, CA to Frankfort, IN) is 1,758.20 mi.
2,115 mi = 3,404.32 kms