2011:220 - THORNTON HALL, KILSALLAGHAN, Dublin

Excavations were carried out at Site 1, Thornton Hall, Dublin, between 13 February and 1 April 2011. This work was carried out on behalf of the Irish Prison Service in advance of the construction of a security barrier around the site of a proposed prison. A programme of pre-development investigations, including a geophysical survey and extensive test-trench excavations, was carried out by ADS Ltd in 2005 (Excavations 2005, no. 543, 05E1355) and 2006; this revealed six areas of extensive archaeological remains as well as a further eighteen areas of isolated archaeological features. Of these, only the northernmost area, Site 1, would be affected by the construction of this perimeter wall. The archaeological remains at this site were identified as consisting of a subrectangular enclosure of 7th–8th-century date. Measuring some 54m in length by 40m in width, it was centred on an east–west-running natural ridge, with a possible ancillary enclosure or stockade to the south and ditches running down the northern and southern slopes. While the easternmost side of the enclosure will not be disturbed, the possibility of preserving the remainder of the site in situ, the preferred option, had been fully explored but found impossible, given the constraints and specifications of the security wall, and therefore preservation by record was recommended.
Topsoil-stripping of the site took place from 13 to 18 February 2011, followed by archaeological excavation from 21 February to 1 April 2011. The excavation results revealed that the line of the subrectangular enclosure had been reinstated at least once, and also identified an entrance to the enclosure at its north-east corner and a possible earlier entrance at the south-west. Probable structural remains, in the form of wall slots, and associated evidence of occupation were identified within the main enclosure; this evidence included a cobbled pathway leading from the entrance to the enclosure interior, a hearth, a drainage gully and two possible cisterns, as well as artefactual evidence including bone pins, a lignite bracelet fragment, a millstone and a large quantity of animal bone fragments.
In addition, the existence of a southern ancillary enclosure was confirmed and nine probable kilns were identified, including one cluster situated at the base of the northern slope of the ridge. The kiln-type features in this northern group were quite large, with flue-like extensions running off to the north; the possibility that they were not grain-drying kilns but were related to industrial activity, perhaps metal-working, is being explored. Numerous features not previously identified during test excavations were also revealed and excavated, including one pit of possible prehistoric date.

Archaeological Development Services Ltd, The Print House, South Cumberland Street, Dublin 2