Canada track:

At the first mill, the road will be
off to the left in a bridge. Keep 
right, hit the ramp, and go through 
the windmill to land back on the road.

At the second mill, there will be 
boxes stacked to the left. Go behind
them and go up the ramp. Be sure you 
land on the logs after it (if you do 
not, you will fall in water and 
restart on the road).