A few links. The first is to a picture of a rock pile in the area of Pennsylvania where I grew up. The Pinnacle is a spot along the Kittatinny Ridge of the Appalachians where the ridge doubles back on itself. At the end of the kink is a rock outcropping that forms a lookout. It is a tradition among at least some hikers to bring a stone to add to a large rock pile there. Here's a picture with hikers. And here is what the Pinnacle itself looks like, speaking of rock piles. The landscape in the far background there is where I grew up.
Also, my brother Andy sent me a link to pictures of a site in Schuylkill County, called Boxcar Rocks or the Chinese Wall. It's hard to tell in the pictures but at places it is as much as 60 feet high. Some good pictures of it are here and here, and if you use the links in the top box at the right, you can see more. Note the boulder that looks like a standing female figure in the second photo.