1995:237 - TRIM CASTLE, Trim, Meath

Limited archaeological excavations were carried out at Trim Castle between 10 April 1995 and 12 January 1996. The work was undertaken under public tender to the Office of Public Works and was designed as part of the extensive and ongoing conservation and presentation work in the castle.

Two main areas were initially excavated, namely around the outside of the keep and along the eastern curtain wall. Additional areas were later excavated in the interior of the keep itself and in the area of the Great Hall and curtain walls at the north-eastern side of the castle.

Excavations were previously carried out in a number of areas of the castle during the 1970s (P.D. Sweetman, P.R.I.A., 78C, No. 6, 1978).

Area 1 - vicinity of keep
A long period of occupation with many changes in structures was uncovered.

Pre-Norman occupation
Scant evidence of probable prehistoric activity occurred in the form of a small number of pits and stray finds of flint artefacts.

A number of levels of early medieval occupation also occurred. A small oven was superseded by a post-and-wattle building with a metalled floor. At a later period a large wooden barn was built in this area. It burnt down and considerable quantities of burnt oats and wheat were uncovered.

The 1172 ringwork
Evidence of the first Norman defences on the site consisted of the remains of a ringwork with an earthen bank, timber palisade and external ditch. This ringwork dates from 1172 and is described in the medieval Song of Dermot and the Earl. Part of the stone footing of a contemporary timber-framed building survived within it.

Stone castle
The construction of an imposing stone keep, located in the centre of the ringwork, was begun c. 1175 and continued into the earlier part of the next century. Excavations within the keep revealed part of the original internal division, which was later rebuilt. Evidence of the construction sequence of the external keep walls was also uncovered. A remarkable survival was a shallow circular trench which had been marked out by ropes to define the size of one of the towers of the keep.

The excavations demonstrated that the entrance tower and the two rooms in the main block of the castle had suspended wooden floors with unlit cellars beneath them and that there never was a motte on the site.

After the erection of the keep the ringwork ditch appears to have been enlarged and deepened, in many areas being cut into bedrock.

From the latter part of the 13th century onwards alterations were made and structures added to the outside of the keep. This began with the addition of a massive battered plinth in the later 13th century. It included a forebuilding guarding the entrance.

In the early 14th century a rectangular building with unusual internal arrangements along with a walled enclosure, defended by a round tower at one corner, was added outside the entrance to the keep. The remains of a stone-revetted entranceway, which was guarded by a drawbridge, survived on the inner side of the ditch.

The ditch was deliberately backfilled later in the same century except at the west side of the castle, where a large double-flued lime-kiln continued in operation until the end of the century.

A large quarry was cut to a depth of 3.5m into the bedrock on the east side of the castle. It was quickly backfilled with rock chippings before the later 15th century.

During the 15th century a well was constructed in the backfilled quarry. At a similar date the enclosure around the entrance to the castle was enlarged and another corner tower added. The forebuilding to the castle was also enlarged and a stone causeway was built over the backfilled ditch. A small wash-house was erected against the side of the castle, with a drain leading from it down to the river. During the 16th and 17th centuries further small buildings, some with cobbled floors, were added to the keep. The wall of the castle was breached to allow access to the basement of one of the towers, which was refloored at the time.

Within the keep lead-smelting probably related to the 17th-century occupation, and construction of gun emplacements was evidenced.

The final phase of activity evidenced began in the early 18th century with the collapse/demolition of the northern tower of the castle, and continued with the robbing out of much of the battered plinth and stone buildings around the keep. Two lime-kilns dating probably from the 19th century were discovered at the east side of the castle. No doubt much of the stonework of the castle ended up in these structures.

Area 2-eastern curtain walls and towers
Excavations were undertaken over the eastern curtain wall and over the northern end of the western curtain of the castle.

The northern corner of the late 12th-century curtain on the east side of the castle was originally marked by a massive tower which had walls up to 4.7m in thickness (stronger even than the keep). It survived to two stories over basement in height, and remains of arrow-loops, a window and a number of stairs occurred.

South-eastwards from the tower the curtain was of two periods. The earlier phase contemporary with the tower was, until recently, hidden below ground and was pierced by five embrasures with arrow-loops.

The interior and exterior of the high rectangular mural tower north-east of the keep were also excavated.

Between this point and the south-east corner of the curtain only small lengths of wall survived. The presence of another rectangular mural tower was evidenced by robber trenches only.

'Great Hall' and 'Mint'
In the 13th century a large three-aisled building measuring over 31m in length by 20m in width was constructed in the north-east corner of the castle, utilising the curtain wall for one of its sides. The old embrasures in the curtain wall were blocked and the wall was heightened and pierced by five large windows. The building consisted of a hall with a separate room, probably kitchens, at its south-east end. The latter room stood over a large stone-vaulted undercroft with two entrances. One led, via a rock-cut passage and through a doorway in the curtain wall, to the river. It is probable that a wooden jetty lay outside the gate to allow ships to unload supplies. A second entrance led from the south-west end of the undercroft.

Parliaments were held in Trim Castle in the 15th and 16th centuries and probably met in the hall.

The large northern corner tower was also substantially altered in the 13th or 14th century when new embrasures, entrances and a cobbled ramp to the basement were constructed.

In the 15th and 16th centuries further stone buildings with cobbled floors were added to the southern end of the hall, linking it to the next curtain tower-a total length of over 50m of buildings. This latter area was not fully excavated but the buildings had substantial burnt floors and many hearths and may have been the location of the mint which operated in the castle from 1460 onwards.

More buildings and an oven were added to the south end of this structure in the 16th and 17th centuries.

Evidence of the 17th-century military reoccupation of the castle also occurred in this area, where many small hearths for melting lead and a blacksmith's forge were located. The windows of the hall were blocked at this time and gun-loops constructed there and in the western curtain wall of the castle.

Evidence of 18th- and 19th-century activity consisted of a number of human burials, the robbing of walls and the use of another lime-kiln.

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