Jonathan Ceredig Davies, Folk-Lore of West and Mid-Wales
“ Thomas, Greenpark, informed me that there was a moving stone of this kind in the parish of Llandyssul, Cardiganshire. [Contents] TREGARON. At a distance of about three miles from Tregaron there is a ridge running east and west separating Upper and Lower Tregaron. It is called “Cwys yr Ychain Bannog,” the Furrow of the large-horned Oxen. Tradition has it that the “Furrow” was made by two Bannog Oxen dragging along the ground the carcass of a huge reptile which had been killed by the people of the neighbourhood in ancient time. (For more about Tregaron see Lakes.) ”
