Here is a picture of Mary picking her way along the path that leads down from the summit of Blackrock. This trail winds down the hillsides in the back ground and can form a part of a longer hike that follows the ridge tops in this view.
Clicking on the photo will show the detail of the rock layer - metabasalt, in fact - that forms the top of much of the ridge in the Park, and of Old Rag. This layer is visible in the little peak directly ahead of Mary.
In the meantime, here is Mary in the little gap in the rocks. The stone on Blackrock is quartzite, which is actually one of the sea bed layers, as opposed to the metabasalts of Bearfence and Old Rag. That's part of what makes this one interesting, I guess - that the scramble is over these sedimentary rocks as opposed to the metamorphic, previously igneous layers at the other hikes.
Here is a last parting view of the mountain as we began to head back to the car. This photo is taken from a little stretch of the AT, which hikers can follow down from the summit back to the parking lot. There is also a fire road through this area, so a loop can be stitched together, adding a little variety to the outing.