2002:1341 - DUNDALK: (Area 16) Marshes Upper, Louth

Excavations were carried out between 4 March and 10 April 2002, before the development of Phase I of the proposed five playing pitches at the Dundalk Institute of Technology. The area comprised c. 8ha, and nineteen sites were revealed during the monitoring of the topsoil-stripping. Area 16 incorporated six backfilled ditches, which comprised a field system of at least three fields of early medieval date, one 18th-/early 19th-century field-boundary ditch, a small iron-smelting stack furnace, an associated stake-hole and two further pits.

Early medieval field system
This measured 102.1m north–south by 64.2m. The ditch was U-shaped, 2m wide on average and 0.5m deep. The ditch system appeared to have been recut on at least three occasions, with little silting in the final cut, suggesting that it had been backfilled soon after. Bank-slump material indicated that an upcast bank may have been partially faced with field-clearance stone. This, together with further ditches found across the Dundalk Institute of Technology site, comprised a system of rectangular fields measuring c. 50m by c. 80m.

Small amounts of hazel charcoal, worked flint and handmade coarseware (probable souterrain ware) were found in the base of the final recut, concentrated just south of the eastern/northern ditch intersection, perhaps indicating a previous routeway over the ditch. The charcoal yielded a calibrated radiocarbon date of AD 700–900. Very occasional flint debitage, iron slag, bloom and a small iron object were also retrieved from the surface of the ditch fill.

Modern field ditch
A straight, 58.5m stretch of ditch was recorded in Area 16, but it continued to the east, into Area 17. The western terminus remained open, finishing abruptly at a square, brick-built gatepost. The rest had silted up in recent years and had been backfilled as part of the current development. The ditch was U-shaped, 1.4m wide and 0.5m deep and formed part of a larger system of rectangular fields measuring 200m by 140m, laid out between 1782 and 1836.

Stack furnace
The small circular bowl at the base of the furnace measured 0.38m east–west by 0.39m, with a depth of 0.09m. This was filled with iron slag and hazel charcoal, which yielded a calibrated radiocarbon date of 420–200 BC. The natural beneath was heavily oxidised, as was a further patch c. 0.6m to the north-east, which may represent a second furnace. These both formed extremely neat ovals, suggesting that they had been contained by mud-brick stacks. Further iron slag and bloom were discovered in the nearby medieval ditch, suggesting that the upper parts had been levelled. A stake-hole, 0.08m deep, was found 8m to the east, inserted at roughly 45? off the vertical.

Two small pits filled with burnt stone and charcoal were also recorded in a lighting duct c. 60m south-west.

Unit 21, Boyne Business Park, Greenhills, Drogheda, Co. Louth