By car to the Heuvelrug

Are you coming to the Heuvelrug by car? The Heuvelrug is easily accessible because of its location near the large motorways (A12 and A27). The public car parks are signposted on the access roads to the Heuvelrug municipalities. In addition, parking is usually free and you can always go to one of the green entrances or TOP locations. What main cities still provide for that?