As someone who rode Illinois a lot I will say the trails further NE are decent, my close to home ride was from Woodstock to twin Lakes over back through Spring Grove and back to Woodstock, It is always dependent of snow and timing get out early and they are great a day of traffic and they are brutal. Back 15 years ago there were a lot more trails but development forced many to close. I did take few trips out to the tri-county system west and SW of Rockford, there was never anyone on the trails and they were marked very well some were even groomed. In my opinion it is not worth the drive from the twin cities but there is some decent riding in the state.