There are
1,583 mi
from San Marcos, CA to Topeka, KS
That's the driving distance. It would take 1 day 3 hours to go from San Marcos, California to Topeka, Kansas.
The flight distance (direct flight from San Marcos, CA to Topeka, KS) is 1,263.04 mi.
1,583 mi = 2,547.97 kms