There are
1,599 mi
from Thornton, CO to Cayce, SC
That's the driving distance. It would take 1 day 4 hours to go from Thornton, Colorado to Cayce, South Carolina.
The flight distance (direct flight from Thornton, CO to Cayce, SC) is 1,376.85 mi.
1,599 mi = 1.61 kms