Miles between San Marcos, CA and Duncan, OK

There are
1,340 mi
from San Marcos, CA to Duncan, OK

That's the driving distance. It would take 23 hours 47 mins to go from San Marcos, California to Duncan, Oklahoma.

The flight distance (direct flight from San Marcos, CA to Duncan, OK) is 1,104.88 mi.

1,340 mi = 1.61 kms