Sited on the leading eastern edge of a tongue of land defined to the north and south by minor stream valleys, which descends eastwards towards the floodplain of the River usk, cropmarks show the broad ditches of an oval or pennanular henge monument. The henge monument measures externally 48m NW/SE by 46m, with an internal measurement of 36m NW/SE by 31m. The broad ditch varies in width between 6.5m to 9m and is widest along the opposing long sides of the monument. The henge has two opposing entrances, a narrow entrance to the north-west, but a larger gap on the south-east side measuring 8m wide between well-defined rounded ditch terminals. The visibility and shape of the henge entrances varies between the cropmark evidence from 2009 and 2014, and geophysical survey would be the only secure way to recover a plan of the buried monument. LiDAR data shows the surviving earthwork of a low mound within the central and north-west part of the henge.

No internal features can be identified with any certainty. However, immediately adjacent to the henge on the north-east side are two or three lengths of linear ditch of a similar width and character to the henge itself. A similar length of cropmarked linear ditch some 27m long can be seen in the field 76m to the south of the henge.

The monument was discovered during RCAHMW aerial reconnaissance on 11th June 2009 but photographed with far greater clarity on the 30th July 2014 (AP_2014_4183-4189).

In Alex Gibson's 2012 (Gibson 2012, 101, 111, number 30) assessment of henge monuments in Wales, he described the monument thus;

'Description: Aerial photographs have revealed cropmarks of a broad-ditched oval or circular enclosure, c 45m in diameter. The cropmark has evidence for two opposing entrances suggesting that the enclosure was possible a ploughed-out henge monument. Topography: Situated on a north-west facing hillslope immediately above the river Usk near confluence. Interpretation: Henge.' Gibson considers Bwllfa Cottages to be only one of six certain henges from Wales (ibid., 96).

T. Driver, RCAHMW, 12th June 2009 & 27th Nov 2015.

References:

Driver, T. 2009. Bwllfa Cottages Enclosure, in Archaeology in Wales 49, p. 74 & 77 (aerial photograph).

Gibson, A. 2012. What's in a name? A critical review of Welsh 'henges', in: Britnell, W. J. and Silvester, R. J. Reflections on the Past, Essays in Honour of Frances Lynch. Cambrian Archaeological Association. Welshpool, 78-121.