Cropmarks of a later prehistoric enclosure, of Neolithic character, have recently been identified from GoogleEarth aerial imagery flown in May 2020, at Gileston in the Vale of Glamorgan. The month of May 2020 was one of the sunniest and driest on record; it was the sunniest calendar month on record for the UK, and the second driest May in Wales with just 14.3mm of average rainfall (Madge, G. 2020). Although the Covid lockdown prevented any Royal Commission aerial survey, large parts of the country were overflown for vertical aerial survey and images subsequently uploaded to Google Earth. One such batch of images showing extensive May cropmarks were those for the St Athan/Aberthaw area, helpfully dated by the existence of the words NHS/VE/75’mown into grass on the links at RAF St Athan Golf Club ‘ for the 8th May 2020 VE day anniversary.

Among an array of known and newly recorded cropmarks visible on the imagery is a notable addition to the prehistoric archaeology of the Vale of Glamorgan; a possible Neolithic causewayed enclosure at Gileston near Aberthaw. A number of known and possible Neolithic causewayed enclosures have been discovered in the Vale over the years, mostly from aerial reconnaissance (Burrow et al. 2001; Driver 2009; for a review of Early Neolithic enclosures throughout Wales see Davis and Sharples 2017). One exception is the scheduled enclosure at Corntown, Bridgend (NPRN 300311), the site of which was first identified from fieldwalking in 1976 with the cropmark enclosure only subsequently discovered from the air by Chris Musson in the 1990s (Burrow et al. 2001). In addition a previously unsuspected causewayed enclosure was recently discovered by geophysical survey within the later Iron Age hillfort of Caerau, Ely (Davis et al. 2015). Excavations have shown this to date from the 35th to 34th centuries cal. BC and have produced the largest Early Neolithic ceramic assemblage from Wales (Davis and Sharples 2017).

The closest example to Gileston is a possible causewayed enclosure discovered on a bluff above the Thaw valley at Flemingston (NPRN 404651; Driver 2009), north of St Athan, in 2006. A field check by the author confirmed that part of this enclosure survived as a low earthwork on an uncultivated hill shoulder, a rarity in the Vale.

The newly-identified Gileston example was spotted on Google Earth imagery by the author (TD) in 2020. It occupies a low-lying rounded hillock between the hamlets of Gileston and West Aberthaw at 30m O.D. It has an estuarine aspect, lying only 700m north of the shore at Limpert Bay. The site comprises an inner ditched enclosure apparently built of defined segments, with a circular shape flattened on the south side. This main enclosure measures 95m east-west by 91m north-south, enclosing 0.75ha. Some 80m to the east is an angled ditch, similarly segmented, running generally north-south. Whether this linear ditch forms part of a wide-spaced outer enclosure is uncertain. It is worth noting that a pronounced curve in the country lane through Gileston village on the west side could conceivably fossilise the western return of an outer enclosure ditch, now built over with housing.

Toby Driver, Royal Commission, Aberystwyth

Oliver Davis, School of History, Archaeology and Religion, Cardiff University.

References:

Burrow, S, Driver, T and Thomas, D, 2001, Bridging the Severn Estuary: two possible earlier Neolithic enclosures in the Vale of Glamorgan', in: T Darvill and J Thomas (eds.) Neolithic Enclosures in Atlantic Northwest Europe, Neolithic Studies Group Seminar Papers 6, Oxbow Books.

Davis, O.P. and Sharples, N. 2017.  Early Neolithic Enclosures in Wales: A review of the evidence in light of recent discoveries at Caerau, Cardiff.  Antiquaries Journal 97, 1-26.

Davis, O.P., Sharples, N. and Wyatt, D. 2015.  The CAER Heritage Project: A note on a second season of fieldwork at Caerau Hillfort, Cardiff, 2014.  Archaeology in Wales 54, 35-42.

Driver, T. 2009. A Possible Neolithic Causewayed Enclosure at Flemingston, St Athan, Vale of Glamorgan, in the Context of Known and Possible Examples From Wales. Archaeology in Wales 49, 3-10.

Driver, T. 2009. A Possible Neolithic Causewayed Enclosure at Flemingston, St Athan, Vale of Glamorgan, in the Context of Known and Possible Examples From Wales. Archaeology in Wales 49, 3-10.

Madge, G. 2020. May 2020 becomes the sunniest calendar month of record. Met Office website: Monday 1 June 2020.