Towards the north-east end of Cwm Cadlan, a broad shallow valley on the south side of the Brecon Beacons near Penderyn, lies a complex of earthwork features spanning sveral period. They lie in enclosed rough pasture at the moorland edge on the farm of Wern Las. The recorded features comprise a ring cairn, a cairnfield of some 16 stone piles, possible hut circles, areas of cultivation ridges, and linear banks forming a field system containing a possible building platform. The features lie on the south side of the farm in a field which is mostly poorly drained and infested with rushes but with patches of drier ground, with a further feature on the north side of the farm. See NPRNs 408600 - 408608 for individual site records.
The land here is a downhill extension of a ridge, Cefn Sychbant, which extends north-east onto nearby open moorland where funerary and ritual monuments have been recorded along with burnt mounds and extensive evidence for field clearance.

David Leighton, RCAHMW, 30 December 2008

Sam No GM558
Scheduled area includes the remains of a ring cairn within enclosed pasture to the SE of Wernlas Farm. Surrounding the cairn area the remains of at least sixteen field clearance cairns, a possible hut circle, a well-defined plot of ridge and furrow, several stony field banks and a house platform set within a large subrectangular enclosure.
Source: Cadw scheduling description. 03/08/2004 FF

Aerial photography on 10th January 2003 in winter conditions with drifting snow showed relict cultivation ridges and other earthworks in vicinity of cairns extremely well. Negative ref: 2003/5011 - 55; 2003-cs-0157.

T Driver. 19 Aug 2004.