Prehistoric remains

I was walking across the car park with Islay, when a young chap came up to make a fuss of her.
Having made friends, he turned to me. "Where's the nearest stone circle?" he asked. "Is there one?"
I laughed. "There is - but it's yay high!" I held out my hands about three inches apart.
Up on Hay Bluff, on a piece of flat ground just below the summit, is a car park, which is so well used in the summer that an ice cream van regularly parks up there. Very few people notice the stone circle just to one side of the car park, with a magnificent view of the Wye Valley. You really do have to bend down among the heather and search out the rounded tops of the stones. I imagine that originally the stones were taller, and have become earthed up over the centuries. Once you've found a few, though, it becomes reasonably easy to trace out the rest of the circle - and you do feel that you're discovering something that very few people know about.
For something more substantial in the way of prehistoric remains, I suggested the young chap and his girlfriend could visit Arthur's Stone - a Neolithic tomb, and nothing to do with King Arthur apart from the habit of our forefathers of naming anything impressive after a famous hero.