There are
2,676 mi
from Riverside, CA to Lansdowne, PA
That's the driving distance. It would take 1 day 23 hours to go from Riverside, California to Lansdowne, Pennsylvania.
The flight distance (direct flight from Riverside, CA to Lansdowne, PA) is 2,340.46 mi.
2,676 mi = 4,307.06 kms