Although you might be able to access this one from Knob Hill Road, I would not suggest it. It is very overgrown even in the winter. I exited that way a couple of weeks ago and it was not pleasant.
One way to access the cache is to park at the suggested coordinates and go north on the Thorn Hill Trail. It starts on the other side of Knob Hill Road. Follow this until you come to a fence on your right. Just before the fence, make a right and follow a rough trail (part mowed) until the cache is almost directly south of you. At this point it is bushwhacking the rest of the way. Your best bet is to enter the woods at the coordinates given. You might be lucky enough to pick up a deer trail just inside the woods.
Not suggested for kids unless they are pretty rugged.