Used to be plenty of places to ride back in the day. Talking around 1980 or so. Lived in Madison and had tons of trails, most are all neighborhoods with McMansions now. I used to ride trails all the way up to Powder Ridge from my house and only had to cross a few roads all that way.
My last bike was a Suzuki PE 250 that I used to beat the snot out of. We had a good group of guys that rode together but eventually I was the last one with a bike and sort of sucked riding by myself. One trip over the bars when I was out by myself pretty much ended it for me and stayed with cars after that.