From State College, take Rt 26 south 20 miles to Martin Gap Road, which will be on your left.
From Huntingdon, take Rt 26 north past Cornpropsts Mills; if you get to Jackson Corner you’ve gone too far. Immediately opposite Wesley Chapel and Wesley Chapel Road, turn right onto Martin Gap Road.
Take the left onto the bridge, then immediately turn right again. Watch for a Y in the road with a small wooden sign on the right labeled Frew Road. Take the right onto Frew Road. Park at the trailhead for the Standing Stone Trail and Rocky Ridge Natural Area. See the map from the Standing Stone Trail Club [PDF].