Penygaer is a defensive enclosure on a natural, rocky knoll overlooking Aberglaslyn. Of roughly oval plan, it measures 46m east by west by 37m. It is defined by a denuded wall up to 3m thick and natural outcrops, on top of which is a post-medieval drystone wall up to 1.5m high. The interior is uneven and rocky, and no remains of huts were visible suggesting that the site was not permanently occupied. The entrance is on the east side. Integral with the post-medieval wall are two sheepfolds (NPRNs 532899-900).
Additional sources:
Ordnance Survey record SH54NE4.
RCAHMW Air Photo: 965063/70.
Recorded as part of RCAHMW Uplands Archaeology Initiative project, W.B.Horton, H & H, 22/05/2013