This is an interesting photo, taken from near the northern tip of the Carningli upland, looking towards the SW. Cwm Gwaun is in the distance. I'm not sure of the photo source -- somebody put it onto the web.
You can see the embankments from the fortified site, and the roughly rectangular defended area where the Iron Age village was located. But look at the slopes beneath the embankment in the lower middle part of the photo. They are remarkable in that very little detritus or rock breccia has accumulated on them -- and if you look carefully you can see ice-smoothed or moulded slabs outcropping in a number of locations. Elsewhere, on the flanks of the crag, there are considerable accumulations of boulders and scree.
This is no coincidence -- every time there is a glaciation involving the Irish Sea Glacier, the ice comes in from the north (the foreground of the photo) and under that assault most of the superficial debris that might have accumulated is simply swept away. The last time that happened was during the Late Devensian glaciation, around 20,000 years ago. I still think that at the peak of this glacial episode, the whole of Carningli was overriden by ice. There are other apparently ice-moulded features near the summit crags.
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