2002:0607 - KILGOBBIN, Dublin

This site was revealed during monitoring of topsoil-stripping (No. 608, Excavations 2002, 02E0906) associated with construction works for a mixed residential development at Kilgobbin, Stepaside, Co. Dublin. Evidence of 18th-/19th-century land reclamation was uncovered in an area reserved for residential buildings bounded to the south-west and north-west by the townland boundary between Kilgobbin and Newtown Little. An area measuring c. 40m by 30m was fenced off, and excavation took place from 22 to 31 July 2002.

The site is on north-west-sloping ground overlooking the valley of Kilgobbin stream, with rising ground to the north-west. The features identified comprised two burnt spreads, two possible field boundaries and a system of four stone drains. The site was covered by a thin layer of topsoil, 0.15–0.2m deep. The natural subsoil varied considerably in colour and composition, and there were a large number of granite boulders throughout the field. Some attempts had been made in the past to remove stones, as evident from the large number of stone sockets revealed across the area. In the areas monitored along the sloping ground, no evidence of tillage was revealed, the fields having been in use for pasture up to the start of construction. The OS 1843 and 1875 6-inch maps show that the central and western parts of the area saw some land reclamation in the mid-19th-century, and the activity uncovered may also belong to this period.

Burnt spreads
Two charcoal spreads, possibly representing the truncated basal remains of hearths, were found along the south-western side of the excavated area. The smaller one was oval, measuring 0.73m north-west/south-east by 0.6m, and was 0.08m deep. A layer of fire-reddened, burnt stone (granite and sandstone) and burnt clay was revealed at the base of this feature in the south-east. This was partly overlain by a charcoal-rich deposit in the north-west, which contained some small, angular stones. Both basal deposits were 0.02–0.04m deep. A small patch of fine yellow clay overlay both deposits at the centre of the feature. This deposit, 0.02m deep, was loose and contained some burnt clay. The larger spread was subcircular, measuring 1.15m east–west by 1m, with a maximum depth of 0.2m. A layer of orange/red oxidised clay, 0.02m deep, containing some burnt sandstone, was revealed at the base of the feature. This was overlain by a loose, dry, charcoal-rich deposit, which contained several larger pieces of charred wood.

Field boundaries
Two possible field boundaries existed on similar axes (north-east/south-west) south-east of the main area of drainage. Both features cut into the natural, yellow/brown, gravelly clay. The north-eastern cut (F15) extended beyond the limits of the excavated area and was 10.5m long, 0.7–1m wide and 0.2m deep. It was U-shaped in profile, with a flat base and almost vertical sides. A step at the base of the feature in one location may indicate that a spade was used in its creation. The fill was a mid-brown sandy clay of moderate compaction containing some small to medium-sized granite boulders and occasional charcoal flecks. The second cut was c. 12m south-west of the first and c. 2m south-east of F15. It was 8.5m long, 0.5–0.8m wide, 0.15m deep and U-shaped, with a flat to concave base. In some areas the base was uneven, and a large granite boulder (0.6m by 0.2m), set in the natural soils, was partly exposed in the fill. The fill was identical to that of F15. This cut terminated on either side in two features (F4 in the south-west and F12 in the north-east), which may be interpreted as evidence of the former location of trees or shrubs at these points. F4 measured c. 1m by 0.8m, and F12 was c. 1.5m in diameter. Both were shallow and irregular in shape, with several root strands extending from the main disturbance.

Stone drains
The four drains lay in the north-eastern sector of the excavated area, their location corresponding to a change in the underlying subsoil. The subsoil in this area contained a high amount of sand and gravel, and a heavier, less permeable, sandy boulder clay dominated along the upper slopes, resulting in drainage problems in this sector. F14, F18 and F19 were cobble drains, and F21 was a French drain. Granite dominated in all drains, but occasional sandstone, limestone and shale were also present. The cuts of all drains were well defined, U-shaped in section with straight, almost vertical sides and flat bases. There was no surviving evidence of adjoining hedgerows along any of the drains, indicating that these were internal field drains facilitating the removal of excess water. All drains ran toward the field boundary in the north-east.

F14, oriented north-west/south-east, was 35m long, 0.5m wide, 0.3–0.7m deep and still active. F18 was a curvilinear drain, running north-west for 18m before curving toward the north-east, where it continued for a further 7.5m. This drain was 0.5–0.6m wide and 0.3–0.5m deep. It emptied into F14 and belonged to the same period of construction. It was joined by F19 and cut through the earliest drain in the sequence (F21). Both F14 and F18 were filled with small, rounded, tightly packed cobbles (50–150mm), comprising a mixture of granite, limestone, sandstone and shale of local origin. Cobble drain F19 may be only slightly later in date than F14 and F18. It was oriented north-west/south-east, 12.5m long, 0.5–0.6m wide and 0.25–0.5m deep. The stones used to fill the drainage cut were larger (150–400mm) and more angular than those in F14 and F18. The stone fill was overlain by a thin, yellow, gravelly clay capping, 0.05–0.1m deep. Like F14, this drain was still active. French drain F21 was preserved largely intact below a redeposited, yellow clay capping (0.2–0.3m deep). It ran for a distance of 16m north–south, turning toward the south-east, where it continued for a further 13.5m. The drainage cut was 0.5–0.6m wide, and the stone drain was 0.35m deep. Angular granite and sandstone blocks were used for side/capstones. The cavity so created measured 0.2m by 0.2m and remained in reasonable condition in the section excavated. The drain was still active. Like F14, the starting point of F21 was along the rising ground in the south-east.

2 Killiney View, Albert Road Lower, Glenageary, Co. Dublin