There are
2,704 mi
from San Marcos, CA to Pottsville, PA
That's the driving distance. It would take 1 day 23 hours to go from San Marcos, California to Pottsville, Pennsylvania.
The flight distance (direct flight from San Marcos, CA to Pottsville, PA) is 2,300.71 mi.
2,704 mi = 3.22 kms