i grew up around here racing and riding dirt bikes , theres alot of places we used to go that no one ever cared , but no adays seems like they are cracking down hard , so as for legally i dont know where to tell you to go right now , there will be one opening up sometime in the future in millville ,
www.njmotorsportspark.com , theres some really atv parks in the moutains in pa and wv , if you go to the
www.thequadfest.com , and get a link to one of the places up there , i cant remember the name of the mountain itself , i been there and its awesome , i beleive its open all year around but during summer months they do events all the time for the family , you can check out that area .