This is another great image from the Preseli360 drone camera, showing just how rugged the summit is when seen from the S or SW. Jagged rock faces and scree slopes are normally associated with shaded of lee side slopes facing N or NE, but here they face south and south-east. I have pondered long and hard on the explanation for this -- and am convinced that the NW flank of the mountain was "cleaned up" by the overriding ice of the Irish Sea Ice Stream coming in from Cardigan Bay and travelling NW towards SE. The face we are looking at in the photo is the plucked face with features we often associate with the down-glacier sides of roches moutonnees. I think there may well have been a wind-scoop feature here as well, maybe lasting for thousands of years and allowing frost shattering and scree accumulation to proceed more or less unhindered.
And another from Hugh.........
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