1986:25 - DUBLIN: Dublin Castle, Royal Exchange Ward, Dublin

Excavations began here in April 1985 and continued until February 1987.

Bermingham Tower
Excavation was carried out here between Autumn 1985 and Summer 1986. Part of a possible late 12th-century enceinte wall, which had been modified in the early 13th century to form part of the curtain wall, was found close to the SW corner tower (the Bermingham Tower). The Bermingham Tower itself was rebuilt in the 18th century and is still in use, but the excavations did reveal the foundations of a square tower projecting from its base and contemporary with it. The function of this extra tower is uncertain but it may have formed part of the medieval town defences, since the 13th-century town wall crosses the moat and abuts the tower at this point.

A considerable stretch of the town wall was exposed. An arch had been incorporated in the wall, where it crosses the moat, presumably to allow access from the River Dodd which bounds the castle on its southern side. This arch was blocked up by the end of the 13th century. The deposits recorded in the moat range in date from the 13th -18th centuries.
Ann Lynch

Genealogical Office site
An area between the Genealogical Office and Castle Street was excavated during the four months of December '85 to March '86. This area coincided with the outer portion of the castle moat opposite the main entrance. The outer edge of the moat was found to kick in at this point to abut one end of a large rectangular barbican aligned on the main entrance which, itself, was outside the area available for excavation. Only the lower part of the barbican survived and there was a drawbridge pit in it about mid-way across the moat. There was evidence for later medieval repair to the west face of the barbican and post-medieval buttressing work in the drawbridge area.

Powder Tower site
Excavation at this site began in July '86, after the demolition of Blocks 8, 9 and 10, and continued to the end of January '87. The area involved is the north-east corner of the medieval castle. Most of the base of the massive circular corner tower here, known as the Powder Tower, was uncovered. Within the tower a rich 14th-century layer produced pottery, coins and a large amount of scrap iron and bronze. At a lower level within the tower pre-Norman layers were found and clear traces of the eastern ramparts of the Viking town. The earliest of these was a bank with dry-stone facing built on the shore of the Poddle estuary.

A section of the medieval city wall was uncovered where it crossed the moat and abutted the Powder Tower. This wall originally had a large open arch spanning the moat at this point, through which the sea could flow at high tide. The moat was partly rock-cut here and the foundations of the tower were found to be sitting on the rock. In late medieval times the arch was blocked up and this blocking wall was built on about 1.5m of moat fill.

A 21m-long section of the foundation of the north curtain wall was also uncovered and a long narrow strip of Viking-age material immediately inside it. This wall was founded on the boulder clay but its sloping base continued down the inner face of the moat where it rested on a quarried ledge of rock.

Corke tower site
A further area of Viking-age deposits was uncovered in the extreme north-west corner of the modern castle complex, outside the medieval moat and adjoining the area excavated by Dr Ann Lynch in 1985-86. This was found only after the building contractor had moved onto the site and had to be excavated as a salvage operation during August and September '86. Large portions of three successive rectangular post and wattle houses of the usual Dublin type were excavated as well as part of a timber-lined pit. The finds uncovered include a saw frame made from a curving piece of antler and the cross beam of a light, wooden loom.
Conleth Manning