Enclosure, Thomondtown, Co. Dublin
Co. Dublin |
Enclosures
In a broad arable field in Thomondtown, County Dublin, a roughly circular earthwork sits close enough to the M1 motorway to fall within earshot of passing traffic, yet it remains almost entirely invisible to anyone on the ground.
The enclosure does not announce itself with upstanding walls or visible banks. Instead, it reveals itself only from above, as a positive cropmark, a phenomenon where buried ditches cause the crops growing over them to develop differently from their surroundings, producing a ghostly outline readable in aerial photographs and satellite imagery. The enclosure was recorded from Google Earth coverage dated 3 July 2019, and it is through that kind of distant, overhead gaze that its shape finally becomes legible.
What the imagery shows is a sub-circular enclosure with external diameters of approximately 40 metres on the northeast to southwest axis and around 35 metres northwest to southeast, defined by a ditch roughly 2 metres wide. There is no clear evidence of an entrance gap through the bank, which is itself unusual and may simply reflect the limitations of cropmark evidence rather than an original design without an opening. Enclosures of this general type are associated across Ireland with a wide range of periods and functions, from early medieval ringforts used as farmsteads to prehistoric or later ceremonial sites, and without excavation it is not possible to say which category this one belongs to. Fragmentary linear and curvilinear features visible adjacent to the east and southeast suggest the remains of a probable field system in the same area. The site lies approximately 1.25 kilometres southeast of Gracedieu, which contains a complex of ecclesiastical monuments, a proximity that may or may not be coincidental. An unnamed stream runs west to east around 158 metres to the south.
Because the site survives only as a cropmark within an actively farmed field, there is nothing to see at ground level during a visit, and access to the field itself would require the landowner's permission. The most practical way to examine the enclosure is through Google Earth or similar aerial platforms, using the July 2019 coverage as a reference point. Cropmarks of this kind are generally best expressed during dry summers when moisture stress in the soil is most pronounced, making mid-to-late summer imagery the most productive. The record was compiled by Tom Condit and uploaded to the national monuments database in April 2021, and the site reference for the adjacent features is DU008-121----.
