Located on the southern slopes of Mynydd y Betws is an alignment of mostly low, edge-set and recumbent small stones with a few uprights. The alignment numbers 172 stones, apparently unworked, and can be followed over a distance of 700m (roughly south-west to north-east). It can be traced from a large recumbent stone at its south-west end, the largest stone in the row at SN68520974, to a small stony mound 6m in diameter at SN68931033.
The alignment is not completely straight and includes at least 15 conjoined segments. It follows a line between two groups of cairns identified as Bronze Age cemeteries (NPRNs 304006 & 304013) and a nearby platform cairn (304001). Excavations in advance of a local windfarm development failed to produce any artefacts or radiocarbon dating material from the alignment. But three further stones were identified and more may lie beneath the turf (1).
Although closely associated with Bronze Age funerary and ritual monuments, an alignment of this length and character is unusual in a Welsh context but is well documented in the south-west of England, especially Dartmoor.
(1) S.Gerrard 2014, A stone alignment at Bancbryn, Mynydd y Betws, Carmarthenshire. (unpublished report, NMRW archive).

RCAHMW, 8 April 2014