There are
2,168 mi
from Oshkosh, WI to Mill Valley, CA
That's the driving distance. It would take 1 day 14 hours to go from Oshkosh, Wisconsin to Mill Valley, California.
The flight distance (direct flight from Oshkosh, WI to Mill Valley, CA) is 1,809.90 mi.
2,168 mi = 3,488.37 kms