There are
1,757 mi
from St Peters, MO to Hayden, ID
That's the driving distance. It would take 1 day 6 hours to go from St Peters, Missouri to Hayden, Idaho.
The flight distance (direct flight from St Peters, MO to Hayden, ID) is 1,446.76 mi.
1,757 mi = 2,828.37 kms