Back in 2006 a new rule required Forest Service units to designate roads open to motor vehicles. In order to let the public know where motor vehicles are allowed, the agency was tasked to create maps of each individual National Forest. On those maps you’ll find a legend indicating where and when motor vehicles can be driven – and camp.
Most of these maps can be had for free from the offices of each individual forest. However, you can also download these maps from the Internet. How do you find them? It’s easy – simply search like this: “X National Forest motor vehicle map,” and put the name of the National Forest in place of the X.
This helpful hint came from http://www.rvboondockingnews.com/2014/02/free-maps-help-you-find-boondocking.html
The maps are huge. I have copied bits and pieces. Have you seen these maps?