Heading south on route 10 from Winchester, pass through the stoplight in Winchester. Proceed for around 3 miles or so. The road eventually bends widely to the right. Park at a large pullout on the right side of the road. Immediately cross the road and follow a blue-blazed path to a river. Follow the trail and eventually right after about 50 yards. Head up a hill. The boulders are all in this general area.