1998:346 - KILKENNY: Abbey Street, Kilkenny

A 4m-diameter circular shaft for a manhole was excavated in Abbey Street, Kilkenny, 0.6m to the north of the medieval walls and close to the 13th-century Franciscan Abbey, known as the Black Abbey. The Black Freren Gate, the only remaining medieval gate in Kilkenny, stands 25m to the east of the site. Martin Reid previously carried out excavations in the immediate area under the same licence number (Excavations 1996, 56).

The manhole formed part of the Kilkenny Main Drainage Scheme and was excavated down to a final depth of 4.5m below present ground level. In order to restrict any possible ground movement and subsequent damage to the nearby city wall and its foundations it was decided to construct the manhole by means of segmented concrete rings, placed on top of each other and bolted together. A bracing structure and monitoring system were constructed on the city wall in order to monitor any movement.

Below the modern concrete road surface and hard-core an east-west wall spanned the width of the shaft on the north side. An east-west drain, formed by cobbles, ran parallel to this wall, and it was apparent that this drain skirted a cobbled roadway, of which only the northern edge remained. Below this cobbled road a metalled surface was revealed containing animal bone, post-medieval pottery and one sherd of medieval pottery. The archaeological strata were severely disturbed on the southern side of the shaft by the insertion of three modern drains.

However, the northern portion of the manhole revealed varying layers of rubble, some containing medieval pottery, together with a quantity of animal bone, all underlain by a black, sterile layer. The east-west wall appeared to be resting on the foundations of an earlier wall. When these two walls were removed a layer of redeposited soil was uncovered. A layer of large, roughly quarried stones, which filled the northern section of the shaft, underlay this. On removal of these stones large wooden piles were revealed, closely packed together and averaging 2m long. All of the piles had a slight diagonal angle and lay in a north to north-east direction. The piles were concentrated in the northern section of the shaft and ran into the northern side of the manhole. The piles, with well-pointed tips, had been inserted into a very peaty, bog-like soil, which was very dense. This peaty soil came down to mid-brown, natural gravel at a depth of 3.8m.

It is thought that the walls may be the remains of 18th/19th-century houses that fronted onto the north side of Abbey Street and that the cobbled drain and road may be contemporary with the upper wall. The layer of large stones and the wooden piles appear to be attempts to consolidate a wet, boggy area. The Bregagh River currently lies only 20m to the north of the site. A dendrochronology date from the 12th century has been received in relation to the wooden piles, which are of oak, and it appears that they may be contemporary with the initial Anglo-Norman presence in Kilkenny from 1172 onwards.

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