There are
1,880 mi
from Thornton, CO to Holyoke, MA
That's the driving distance. It would take 1 day 10 hours to go from Thornton, Colorado to Holyoke, Massachusetts.
The flight distance (direct flight from Thornton, CO to Holyoke, MA) is 1,683.83 mi.
1,880 mi = 1.61 kms