There are
2,169 mi
from Mill Valley, CA to Oshkosh, WI
That's the driving distance. It would take 1 day 14 hours to go from Mill Valley, California to Oshkosh, Wisconsin.
The flight distance (direct flight from Mill Valley, CA to Oshkosh, WI) is 1,809.90 mi.
2,169 mi = 3,490.84 kms