There are
1,010 mi
from Thornton, CO to La Puente, CA
That's the driving distance. It would take 17 hours 39 mins to go from Thornton, Colorado to La Puente, California.
The flight distance (direct flight from Thornton, CO to La Puente, CA) is 821.50 mi.
1,010 mi = 1.61 kms