There are
1,995 mi
from Markham, IL to Monrovia, CA
That's the driving distance. It would take 1 day 10 hours to go from Markham, Illinois to Monrovia, California.
The flight distance (direct flight from Markham, IL to Monrovia, CA) is 1,721.14 mi.
1,995 mi = 3,211.21 kms