Routes that are open for all OHV's are depicted on the MapViewer and GPS Maps as green lines.  In some places, single track routes are shown as yellow lines, and routes less than 50 inches wide are shown as orange lines. Routes restricted to street legal vehicles with licensed drivers are shown as blue lines.

This might not be noted in route files that are downloaded to your computer.  However, such restrictions are indicated on trail signs.  Therefore, ALWAYS follow the signs and conditions on-the-ground, even if they are different than what is depicted by the OwlsheadGPS Project.