This is definitely a locals trail system, and despite the complete and utter lack of trail markings, it appears to be legal (as far as I can tell). While I wouldn't recommend driving from out of town to check this trail out, for those living nearby I am sure it is a real gem. There are some great trails snaking through the forest here, but it is truly a massive spiderweb. If you are a first timer here, just start exploring. You will come out eventually. When you do, head back in and try a different fork in the trail. Wash, rinse, and repeat!
Take the Ashland exit off of I-95 and follow Hwy 57 west for about 1.5 miles out of town. Turn left at Poor Farm Park (there is a middle school there + soccor fields). Park in the gravel lots. trails begin on either side of the woods.
http://www.tripleblaze.com/trail.php?c=3&i=220