2020:573 - 40 Knockbracken Road South, Lisnabreeny, Belfast, Down

In advance of development, a section of a partially upstanding rath ditch was uncovered. The site was located on the crown of a hill overlooking the Lagan valley to the west at a height of 150m. On the eastern part of the development site was a ruinous dwelling, first visible on the 2nd edition Ordnance Survey (OS) map (1860). A level 2 historic building survey was conducted on this structure prior to its demolition. No flooring or cellars were uncovered. The tiled areas to the south, and the adjacent areas, which were the remains of the original north to south running building on site (first visible on the 1st edition OS map) that had been partially replaced by the 2nd edition building, were cleaned, photographed and planned. The remains of the floors of the building shown on the 1st edition to the south were lifted to try and establish construction methods and determine if there were any earlier surviving floors or building remains under the 20th-century floor tiles that comprised the visible surviving remains of this structure. When these were lifted there was no evidence of any earlier floors or remains, just undisturbed red glacial clay. It seems that this building had been constructed directly onto the subsoil. To the west of the 1st edition building an area of mortared unperforated brick and modern hardcore was exposed, the remains of a filled-in brick-defined well. The western arc survived and would have bounded a well around 3m in internal diameter if intact. Strangely, the bricks which defined the edge of the well only existed in three very badly laid upper courses, the rest was clay- or rock-cut. The bricks used to construct it were handmade and unperforated, measuring 9 inches by 4 inches by 3 inches, and were identical to those used in the house shown on the 2nd edition map.

When the concrete farmyard in the western part of the development area was broken and lifted it exposed a curving dark deposit which appeared to cut the orange glacial clay subsoil. It ran northwards from the entrance of the modern cow byre in a westward curving arc towards the upstanding remains of the rath bank. Upon cleaning, the exposed section of ditch were found to be was divided into two parts, separated by a narrow causeway; the southern section just north of the byre was 17.5m in length and 5m in width, with a rounded northern terminus. The northern section to the north of the causeway was exposed for a distance of 7m to the edge of the development area and was 5m in width with a rounded southern terminus. The two sections of ditch were linked at the termini by a narrow stone-filled slot trench which presumably acted as a drain. A single section was excavated across the southern portion of the ditch, 11m to the north of the byre. The section was 2m in width and just over 7m in length. The upper fill of the ditch was heavily disturbed, being a mixture of building foundations, probably dating from at least the 2nd edition map onwards, drains, redeposited bank material and the accumulated upper ditch fill/garden soil. The rath ditch was cut into red glacial clay and was 5.2m in width and 1.5m deep and had a steep outer edge with a stepped inner edge and a flat base. The two termini of the ditch were separated by a causeway or entrance, aligned approximately north-east. Upon initial exposure the entrance was thought to be no more than 1.2m in width, crossed by a stone-lined drain. This area, along with the complete upper area of the ditch, was removed to the working level, a drop of 0.3m which widened the entrance causeway to 1.6m, a much more useful width to allow for easy access and egress of domestic animals such as cattle and horses.

The only artefacts recovered during the excavation of the trench across the rath ditch were 8 sherds of Black Ware dating to the late 18th or early 19th century. These were recovered from the base of F9, indicating that the removal of the bank and filling of the ditch probably took place around that time consistent with the map evidence. As no dating evidence relating to the period of use of the rath in the form of artefactual evidence was uncovered during the investigation, samples were taken from the peat-rich basal layers F6 and F7 and processed to attempt to recover charcoal or other organic material to allow a radiocarbon date to be returned. This was unfortunately not possible as both samples were lacking in the required material. It is therefore not possible assign the rath to a specific date in the early medieval period, though it is most likely to date to the period between AD550 to 900.

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