I cannot speak for the Marathon Co portion of the Mtn Bay, but did ride to the border of it in Shawano Co on Sat afternoon. Rode from Lyndhurst to Eland and back. Flat and smooth with only a couple of thin spots, which were closer to Eland. We saw a few other sleds on the Wiouwash heading from Birnamwood towards Tigerton. Not sure how that is either, but looked good where the trails intersect.
