My GF and I were coming back from Mollidgewock SP and heading towards Portsmouth and decided to take the long way home. I looked at the Map and saw this rd. , Jefferson Notch Rd, which connects rt.2 (from the north) and 302(to the south). We came in from the rt. 2 side and followed Jefferson Notch rd. to a little dirt rd with a sign that said local traffic only. We followed it a little further and came to a gate (closed winter season) where there was a guy getting ready to hike with his dog. He said, " that the road is closed due to trees being down but he hiked the 9+ miles a week ago and he didn't see anything." Mentioned that they usually open it in late june early july. (we were there in mid-june) But the road looked really cool and it is def. on my list to check out when we head back up in Sept.
If you have a New Hampshire Atlas & Gazeteer it is on PG 48 J4. It looked narrow but definitely passable. On the map it looks like a fairly substantial road (based on the solid red line) but I assure you that coming from the rt. 2 side that it was a dirt road and very off the beaten path.
If you check it out please report back as I'm very interested in exploring it myself.
Scott