I have driven down the B4270 many times and always have a quick look to see if I can spot the barrows. From the road there is one that can be seen as a shallow rise in the field. The rest are not obvious from a 'drive by' view.
The Coflein record recognises five round barrows here, pretty much along the line of the road.
I was reading about a Gwyllgi - a supernatural black dog - in Wirt Sikes's 1880 'British Goblins', and it doesn't seem unreasonable to suppose it is associate with these barrows, as they are frequently paired with barrows in other districts. He says:
The lane leading from Mousiad to Lisworney-Crossways [this must mean Moorshead to Llyswyrny and Crossways] is reported to have been haunted by a Gwyllgi of the most terrible aspect. Mr Jenkin, a worthy farmer living near there, was one night returning from market on a young mare, when suddenly the animal shied, reared, tumbled the farmer off, and bolted for home. Old Anthony the farm servant found her standing trembling by the barn-door, and well knowing the lane she had come through suspected she had seen the Gwyllgi. He and the other servants of the farm all went down the road and there in the haunted lane they found the farmer, on his back in the mud. Being question the farmer protested it was the Gwyllgi and nothing less, that had made all this trouble, and his nerves were so shaken by the shock that he had to be supported on either side to get him home, slipping and staggering in the mud in truly dreadful fashion all the way.
It is the usual experience of people who meet the Gwyllgi that they are so overcome with terror by its unearthly howl, or by the glare of its fiery eyes, that they fall senseless. Old Anthony however, used to say that he had met the Gwyllgi without this result. As he was coming home from courting[..] late one Sunday night[..] he encountered in the haunted lane two large shining eyes, which drew nearer and nearer to him. He was dimly able to discern.. what seemed the form of a human shape above, but with the body and limbs of a large spotted dog.
He threw his hat at the terrible eyes, and the hat went whisking right through them, falling in the road beyond. However, the spectre disappeared, and the brave Anthony hurried home as fast as his shaking legs would carry him.