Cross country ski trail much of which is posted with MTB access. (watch maps as a few segments are hike only) It's generally wide turf trail with a few parts gravel double track and some almost single. (cross bike will go well if conditions are dry.) Some good steeps and anything moving away from the lake is going to be brutal. There's paved path paralleling the whole thing, which, if anything is harder in terms of long climbs. Some good exercise not much tech. And I don't know what predators are out there but they eat birds and deer.