My older son and I biked the Four Season Adventure Trail today from Corinna to Dexter. There is a small parking area in downtown Corinna from which we headed north. Although it had a number of puddles, the trail was mostly flat and well packed, although there was a section just north of Lincoln Mills Road where the trail was softer dirt.
It was a cold but beautifully sunny Sunday. As such, there were a number of ATV riders out on the trail, although for the most part they were courteous.
This section of trail travels through forests and wetlands and has a remote feel to it.
Here is a map of our ride.