Miles between Thornton, CO and Boone, IA

There are
686 mi
from Thornton, CO to Boone, IA

That's the driving distance. It would take 12 hours 4 mins to go from Thornton, Colorado to Boone, Iowa.

The flight distance (direct flight from Thornton, CO to Boone, IA) is 597.70 mi.

686 mi = 1,103.44 kms