Easy one this. As you drive along the A40 through Bwlch the road bends to the left and the stone is easily seen in the large field to your left. There are plenty of parking places in the village and it is only a short walk to the stone. I am no expert by any means but it gave me the impression of a rubbing stone?
Standing Stone (1.8m tall) in Bwlch village. According to Coflein, traces of Ogam and Latin inscriptions have been claimed, but not substantiated, and all markings on the stone are attributed to recent agricultural usage (used as a cattle rubbing post).