2001:434 - BALLYOGAN RECYCLING PARK, Jamestown, Dublin

The site is located on land due to be developed as part of the development of Ballyogan Recycling Park. The Pale Ditch itself appears as a wooded bank flanked by a double ditch running some 55m east–west in a straight line. It is situated between a sloping meadow to the north and a flat marshy area bounded by the Ballyogan Stream to the south. The earthwork was built at the point where the slope ends and the wetland begins, the northern inner side being on higher ground than the southern outer one.

The area has seen much development in recent years and is bordered to the south and east by the Ballyogan Landfill site. Two of the three existing trackways which breached the Pale Ditch were due to be developed into roadways. This entailed the machine excavation of a 7m-wide strip through the centre of the gaps, which would destroy the existing features. They were therefore hand-excavated prior to the commencement of road construction. Two cuttings of 7m by 15m were proposed. Cutting 1 was at the western end of the preserved stretch and Cutting 2 was at the easternmost breach near the centre of the stretch.

The stretch of the Ditch at Jamestown, the subject of this investigation, was built by the Walsh family to connect their castles at Kilgobbin and Carrickmines (currently under excavation by Mark Clinton; see Excavations 2001, No. 335), which were some 3km apart. Local historian Rob Goodbody has identified traces of the Ditch close to Carrickmines Castle, and documentary and cartographic evidence suggests that it also existed near Kilgobbin Castle. It would seem, therefore, that this part of the Pale Ditch was completed and much of it has subsequently been levelled.

Cutting 1 (16m x 7m) was established through the middle of the western gap through the Ditch. This was the area investigated by Laurence Dunne and Martin Reid in 1998 (Excavations 1998, Nos 203–4, 98E0119) and was very disturbed, with a recently constructed sewer pipe running through it. Despite the disturbances here it is still possible that traces of the fosses still exist since the ground level has been built up to the south, above the level of the low-lying marshy ground. The area was wet and foul and it was established that this was due to raw sewage draining into it from a damaged septic tank upslope. On being informed of the situation, Dúchas requested that the work on this cutting be discontinued on Health and Safety grounds. However, future construction work here should be monitored.

Cutting 2 was excavated through the centre of the third breach, 235m east of Cutting 1. It measured 14m by 7m, the northern limit being c. 1.5m higher than the southern. The surface consisted of a very compact mixture of stones, clay and topsoil which had recently been laid down to provide a firm surface. Owing to the compacted nature of this deposit it was decided to remove it by machine. Once this was done, the line of the two east–west fosses could be discerned, interrupted by a leachate pipe trench and the previous archaeological test-trench, running parallel to each other north–south through the centre of the cutting. The excavation then proceeded by hand, the test-trench being emptied first in order to establish the precise location of the features and their stratigraphic sequence. These features were then fully excavated within the limits of the cutting.

Both fosses were cut through a compact, moderately stony, yellowish-orange natural clay which had some iron flecking. The bases were cut into an underlying moderately stony, medium brown, natural silty clay. The north fosse was the smaller of the two ditches, being 1.8–2.2m wide and reaching a depth below the modern ground surface of 1.1m. It was straight and fairly regular and was V-shaped in section with steep sides and a rounded narrow base. The lowest fill was disturbed, particularly by tree roots, contained modern finds and must also be relatively modern in origin.

The south fosse was straight and fairly regular with a width of 2.2–2.4m. The sides were steeper and more substantial to the north and had a longer, gentler slope to the south. The base was narrow and rounded. It reached a depth of 1.2m from the modern ground surface. The lowest fill was disturbed by roots and flecked with yellowish sand derived from the subsoil. Modern pottery and metal were found in this fill, which was similar to that above it. The dimensions of the southern fosse accord well with those previously recorded on other parts of the Ditch. This is the only part of the Pale Ditch where the north fosse has been excavated.
All the fills of the fosses were modern in origin, and despite the fact that the bank was well eroded, no traces of early silting were observed. This is probably due to the use of the fosses as a field boundary and drainage ditches and the need to clean them periodically. The fosses are cut into hard boulder clay, and digging out by hand of their soft silts may have hardly altered their contours. The north fosse in particular drains a large area and the bank prevents this water from draining away naturally into the wetland and stream. The action of floodwaters could therefore have washed out deposits at times.

Although the bank had been destroyed within the bounds of the cutting, its base still existed between the double ditch. It was 4m wide at ground level, where it had been cut off. This falls within the range already recorded in other places, but the different levels at which these measurements were taken do not allow a direct comparison. The existing bank lay just outside the area of the cutting and the opportunity was taken to record it. It reached 1.05m above ground level on the north side and 1.75m above ground level to the south. This contrast was also observed when measuring from the top of the bank to the bottom of the fosses. On the north side this gave a difference of 1.95m and to the south 2.9m. The bank has steeply sloping, rounded sides and a rounded top offset to the northern side with a flat slope towards the south. It was very eroded and thickly overgrown with trees and shrubs. No evidence of a palisade trench was observed but this could have been destroyed by erosion and the tree root activity.

The fact that the Ditch is well built here shows that the Walsh family took its construction seriously and were able to apply themselves to it effectively. This part of the Pale was close to the Wicklow Mountains, haven of the O’Byrnes and the O’Tooles, who frequently raided the south Dublin area, and a defensive barrier here was probably a priority.

Apart from the three openings that have been made through it, this stretch of Pale Ditch is very well preserved, with the bank standing to a height of 2m in places. The earthwork conforms well to the building specification of 1494 which called for a double ditch with a high bank between them, 6 feet high. The outer fosse is more substantial than the inner one. The ditch is a good example of using natural defences to boost the man-made ones. The slope enhances the height of the bank and the marshy ground and stream augment its defensive qualities. The view from the bank to the south and east would have been far more extensive before the landfill site was established.

Unfortunately, little information about the fosses could be gained from their fills, which had been disturbed in modern times. The excavation took place on a disturbed part of the Ditch and some undisturbed fills may exist elsewhere along this stretch. Although the Pale Ditch is a well-known monument which has even given a common phrase to the English language, relatively little is known of its extent, line and degree of completion. It is to be expected that monitoring of the increasing development in the commuter belt around Dublin in the future will identify further stretches of this important monument.

Windsor House, 11 Fairview Strand, Dublin 3