There are
2,707 mi
from San Marcos, CA to Norristown, PA
That's the driving distance. It would take 2 days to go from San Marcos, California to Norristown, Pennsylvania.
The flight distance (direct flight from San Marcos, CA to Norristown, PA) is 2,346.36 mi.
2,707 mi = 4,356.72 kms