There are
2,100 mi
from Niceville, FL to Walnut, CA
That's the driving distance. It would take 1 day 12 hours to go from Niceville, Florida to Walnut, California.
The flight distance (direct flight from Niceville, FL to Walnut, CA) is 1,842.12 mi.
2,100 mi = 3,378.91 kms