2019:763 - Grange Castle, Dublin

Archaeological monitoring and excavation was carried out between 26 February 2019 and 04 September 2019 during the contractor’s works on the site of Grange Castle, Co. Dublin. Grange Castle is being conserved and developed as a public amenity by South Dublin County Council. The castle is a recorded monument, DU017-034, and is a Protected Structure, 11208013 on the NIAH register.

The castle, which is situated within Grange Business Park, is a historic site in a dilapidated condition. It is a tower-house of probable 15th/16th-century date which was modernised and extended by a later building and a series of outhouses no longer extant. The plan for the castle building is to conserve and stabilise it and to improve the presentation of its site so that the castle, positioned among new gardens and walkways, can be visited by members of the public.

The site was divided into Area 1, the field to the north-east of the castle and Area 2, the area of the castle and its ancillary buildings. All the features of archaeological interest were concentrated in Area 2.

Area 1
Landscaping works in this field involved the construction of a paved footpath with associated light ducting and drainage trenches either side of it. The trench for the footpath extended across the entire length of the field from the north-eastern corner to the south-western corner. The width of the trench measured 10m north-west/south-east while the depth varied throughout its length.

Previous archaeological test trenching in this area in March 2018 under the existing licence revealed that a number of extensive deposits of soil were dumped here on top of the original ground level at some point in the recent past, perhaps from construction work at one of the nearby buildings. As a result of this the central, northern, eastern and southern areas of the field were higher than the western and south-western area, as well as of the surrounding fields, and most of the deposits contained modern refuse material.

Landscaping works carried out during the on-site conservation and development project revealed the same soil profile, with most of the deposits excavated containing modern refuse material and subsoil only reached in the western, lower half of the field. No finds or features of archaeological significance were present.

Area 2
Ground works in the area immediately surrounding the tower-house involved the excavation of trenches for the pathways and associated ducting and drainage as well the ground works associated with the proposed gardens, flower beds and seating areas. While most of the trenches revealed nothing of archaeological significance, a number of features and walls associated with the outbuildings surrounding the castle were recorded. These included the remains of two outhouses or farm buildings to the north-east of the tower-house, an outhouse or farm building and three cobbled surfaces to the immediate east, fragments of two stone walls to the immediate west of the eighteenth-century Georgian house, the remains of five further stone walls, a brick wall, a well, and fragments of brick and cobbled surfaces to the north of the tower-house, as well as a possible paved canal or fishpond structure within the stream also to the north of the castle. It was mainly the lower courses of the walls that survived and they were generally constructed with roughly hewn limestone blocks with dimensions ranging from 0.35m x 0.2m x 0.2m to 0.2m x 0.15m x 0.03m to 0.14m x 0.15n x 0.05m in size and bonded with lime mortar.

The remains of buildings to the north-east of the tower-house appear to be those represented on the 20th-century O.S. maps while the walls and floor surfaces of the outbuilding depicted on Gabriel Beranger’s map of 1773 were uncovered to the immediate east of the tower-house. This latter area included three cobbled surfaces varying in size from 17.5m by 3.5m to 10.6m by 4.4m to 3m by 1.5m length by width. The cobbles survived in relatively good condition and were preserved in situ to be left open to the public as part of the landscaping project. The lower courses of the northern and southern walls of this same outbuilding were also preserved in situ.

Monitoring to the west of the Georgian house revealed fragments of two east-west orientated stone walls in a north-south ducting trench while ground works to the north of the site uncovered a stone-lined well and a number of walls and surfaces associated with the farm buildings and outhouses surrounding the castle.

While the walls and cobbles and well were features related to normal everyday activity in the early modern/modern period, one feature which was very unusual was the culvert/drain/pond feature at the north of Area 2. The stream in this area was culverted below a stone structure with a brick-lined window. During archaeological monitoring of the removal of modern backfill from the area to the east of the culverted section of this feature an east-west orientated flagstone floor bounded by two limestone walls to the north and south was uncovered. Situated at the base of the ditch the flagstone floor measured 3.65m in width north-south and was constructed of medium-large irregular and sub-rectangular shaped flat slate stone ranging in size from 0.34m x 0.22m to 0.42m x 0.35m to 0.9m x 0.6m length by width. The total length of floor measured 21.5m east-west, extending all the way to the culvert structure to the west.

The nature of this culvert structure as a whole, from the north-western corner of the castle grounds to the eastern edge of the paved floor is unclear. It may have constituted a paved canal or fishpond. These were common features in castles, monasteries, manor houses and country houses from the medieval right through to the post-medieval and modern period.

Where structural remains were discovered these were largely left in situ or rebuilt and ultimately incorporated into the overall landscaping project. All finds including pottery were identified as post-medieval in date and there were no medieval features or artefacts discovered.