The trail follows NH Route 12 and then Quarry Road south and east from Troy Village. Leaving Quarry Road, it climbs to the summit of Fern Hill, dips down to a tributary of Quarry Brook where it meets the side trail to the Gap Mt. South Parking Lot.
From Troy Center proceed along the sidewalk on Troy’s main street southeast along the southern end of the Village Common to NH 12 and a brook bridge crossing. Cross the highway to a sidewalk on its northwest side and turning right (S) continue along Rt 12 to the point where Quarry Rd. bears off to the left at 0.5 (11.4) miles. Bear left onto Quarry Road. The trail continues straight ahead uphill to an abandoned section of the road, where the much used gravel road turns left at 1.2 (12.1) miles. There is a fine spring to the right opposite the road turnoff and a few yards east of it. Go straight ahead up the abandoned road. (Do NOT use the driveway to the left of the abandoned road.) Near the top of Fern Hill at 1.4 (12.3) miles the road bears right and the trail immediately turns left up the bank and over a low stonewall. The trail goes straight ahead and downhill crossing two stone walls. At 1.5 (12.4) miles the trail veers to the left continuing downhill through a rocky area. At 1.7 (12.6) miles a yellow-blazed trail comes in on the right just before a brook crossing.
This side trail leads 0.4 miles to the Gap Mt. South Parking Lot. This parking lot is maintained by SPNHF and can be reached as follows: Coming south from Troy on NH12, turn left on Gap Mountain Road about 2 miles south of Troy. Follow this road, bearing right at the first fork. At 0.8 miles, take a sharp left (sign pointing to Gap Mt). The parking area is about 0.1 miles on the left. If coming north on NH 12 from Fitzwilliam do not take the first Gap Mountain Road (0.25 miles north of NH 119) but continue to the second Gap Mountain Road about 2 miles from NH 119 on your right. If accessing the M-M Trail from this parking lot, do not attempt to reach the trail by following Gap Mountain Road north. This access to the Trail and Gap Mt crossed private property and is now permanently closed.