1999:252 - KILMAINHAM: Dept Master's House, Royal Hospital, Dublin

Monitoring took place of the refurbishment and extension of the Deputy Master's House, Royal Hospital, Kilmainham, from August 1998 until February 1999. This house is within the grounds of the present Royal Hospital, erected in the 1680s and built as a hospital and refuge for ex-soldiers. The general area of the present Royal Hospital is reputedly the site of a Knights Hospitallers foundation, granted to the Knights Hospitallers of St John of Jerusalem by Strongbow in 1174. The church of St Maighnenn of Kilmainham, dating from the 7th or 8th century, is also reputed to be close to the present Royal Hospital, and the Kilmainham/ Islandbridge area is well known for its Viking burial finds. The present Deputy Master's House was erected in 1763 and replaced an earlier flanker (one of four symmetrical flankers of the main hospital).

Initial test-trenches within the basement of the Deputy Master's House and to the north and east of the present house revealed no archaeological structures. However, the presence of some fragments of late medieval 13th/14th-century tiles from the base of a trench to the immediate east of the house indicated medieval activity in the area. Consequently, full monitoring of all the basement excavations and the extensions and improvements to the north and east were carried out.

Within the basement of the house no trace of any earlier foundations that may have been associated with the earlier flanker built in the 1680s was revealed. The extension to the east of the house, which measured 16m x 8m, was brought down to a depth of 2.5m. There was no evidence for any structures pre-dating the construction of the present house, and this area to the east of the Deputy Master's House appears to have served as a general dump for the kitchen, with various layers of refuse containing a small amount of post-medieval pottery and glass being revealed. There was also considerable evidence for the artificial heightening of this area, with layers of red brick, stone and soil having been brought in to level up what appears to be have been a piece of land that sloped markedly to the east.

Close to the east face of the house the general area had been considerably disturbed by the insertion of later drains. A small box drain was revealed at the northern end of this extension. However, it should be pointed out that a fragment of a line-impressed medieval floor tile was retrieved close to the east face of the house at a depth of 2.5m and close to the location of the medieval tile fragments recovered during the initial trial-trenching.

The area to the immediate north of the house, measuring 12m x 12m, was lowered by 0.5–1m in order to provide a flat surface for landscaping. During the monitoring of the work, several walls, running north-south and east-west, were revealed; all appeared to be contemporary with the present house and seemed to form rooms connected to the basement area. However, a very fine, red brick, arched passageway was revealed in this area. This was 4m long, 2.7m wide and 1.4m high and appeared to back onto some subsurface basement rooms added on to the northern side of the house at a later period. The red brick passage terminated where the southern boundary wall of the sculpture garden is now. It was not possible to investigate this feature fully as it was very unstable and was being backfilled immediately. The roof of the structure had been removed at sometime in the past, and the interior of the passage appeared to be covered with soot.

With the exception of the medieval floor tiles, no evidence was found for any archaeological structures on the site, and no further medieval artefacts or finds were recovered. There was no evidence for the earlier flanker on the site of the current Deputy Master's House, although all traces of this may have been removed with the digging out of the foundations for the present house. The impressed floor tiles suggest a medieval presence in the area, but it was clear that they were not in situ. No medieval horizons were found during the monitoring, suggesting that the earlier Knights Hospitallers foundation lies elsewhere on this important site.

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