The linear earthwork known as the Whitford Dyke has been traced intermittently for around 9km, from a presumed northern end to the west of Trelawnyd (SJ 0834 7988) to its southern extent (SJ 1531 7466) beyond the Holywell Earth Circle, a prehistoric hengiform monument. The majority of the upstanding sections have been scheduled on the basis that they were originally thought to be part of Offa’s Dyke, although this has now been discounted and the monument is instead seen as a separate boundary earthwork or short dyke belonging to the early medieval period.
Several sections of the dyke have been the subject of small-scale excavations, initially by Sir Cyril Fox during the 1920s, then as part of the Offa’s Dyke Project during the 1970s and 1980s, and more recently in 2008-9 by the CPAT, with funding from Cadw. None of the sections excavated previously had produced any dating evidence and a further programme of investigation was therefore conducted by CPAT during 2012, again with funding from Cadw.
The 2009 excavations had originally intended reopening one of Fox’s trenches to the north of the Earth Circle, although this proved difficult to locate and instead a new section was investigated in the same area. Fox recorded considerable difficulties in identifying the edges of both ditches, and the recent excavations encountered similar problems due to the variable nature of the glacial till which overlies the limestone bedrock in this area. The western ditch was particularly difficult to determine, although as excavated it appeared to be around 4.2m wide and up to 0.75m deep. The eastern ditch was better defined and measured 3.7m in width and up to 0.55m deep.
In October 2012 a single trench, 25m long and 1.5m wide, was excavated across the earthwork at the southern end of the field immediately north of Ty Griana (SJ 1526 7491) and 300m south of the Earth Circle. This produced no evidence for a surviving bank, although this could originally have been up to 8m wide, but demonstrated that the ditches were between 4.9m and 5.7m wide and up to 0.7m deep. Radiocarbon dating of samples from the lower fills of the eastern ditch unexpectedly produced dates of between AD 1665-1950, presumably indicating a significant degree of disturbance by later activity, perhaps related to nearby quarrying, as was more evident in the section through the western ditch and was also suggested by the limited range of charred plant remains. That the origins of the earthwork belong to an earlier period can only be deduced from its relationship with the late enclosure landscape through which it runs. It clearly predates the present roads and land divisions which are likely to date from the later 18th century, the area previously having been unenclosed commonland, and also predates the 18th-century Holywell Racecourse.
At the north-western end of the monument a trench was excavated across the earthwork near Gop Farm (SJ 0840 7980), in December 2012, to investigate a section which has been thought questionable for some time. The results demonstrated beyond all doubt that what was previously seen as the northern end of the dyke can now be discounted as it is a trackway and associated embankment. This also brings into question the other sections in the village of Trelawnyd, where a low bank along the north side of the A5151 had been suggested as a continuation of the dyke and scheduled as such.
To the north of the Holywell Earth Circle, and south of the A55, a magnetometer survey investigated an area where the line of the dyke had been predicted, but for which no surviving earthworks or cropmark evidence existed. The results failed to identify any potential features associated with the dyke, although other anomalies were present, suggesting that there may always have been a gap in the monument at this point.
As a boundary feature the earthwork runs more or less along the spine of the Flintshire plateau, dividing the hinterland of the Dee Estuary from the Vale of Clwyd. This is not to say, however, that the entire monument is of the same date. The limited excavations undertaken so far have demonstrated considerable variation in the dimensions and preservation of the dyke, perhaps indicating that it was not all constructed at the same time. There is, for instance, a considerable difference between the size and separation of the ditches at Brynbella and the dimensions of the section close to the Holywell Earth Circle. Arguably then, the association between the three main sections of the dyke as proposed here has yet to be established with certainty. Hill and Worthington favour only the more impressive earthworks either side of Brynbella as being part of the Whitford Dyke, although the form of the earthwork adjacent to the Holywell Earth Circle is undoubtedly similar, with a central bank and flanking ditches, and this is perhaps unlikely to be coincidental. Towards Trelawnyd, however, further work is clearly required to establish the form of the earthwork and in particular determine with certainty the presence or absence of any associated ditches.
Further excavations are planned for 2013 to investigate a scheduled section of upstanding earthwork to the south-east of Trelawnyd.
To find out more about CPAT's recent work on the Whitford Dyke download a copy of the report at by following this link to CPAT Report 1182