The 1956 Royal Commission record classed this as an arrow stone:
Arrow stone on the W side of track near Ffridd Newydd, on natural boulder 7ft by 3ft 8 inches. On upper surface of stone are groups of parallel cuts from 10-18cm long.
However, Coflein’s 2004 record is not so sure the markings on this stone are even artificial (unlike Arrow Stone II):
A stone on the west side of the track near Ffridd Newydd. It is a natural boulder measuring 2m by 1m and on the upper surface of the stone are groups of parallel cuts from 10-18cm long.
The features on this stone are due to natural geological weathering, often found on basaltic rocks.