2003:375 - CASHLANDOO, Glebe, Derry

As part of the archaeological mitigation for a new foul sewer on the outskirts of Portstewart in the townland of Glebe, Co. Derry, a desktop survey followed by supervision of topsoil-stripping along the route was undertaken. The desktop survey had revealed that the proposed route would have taken the foul sewer close to a monument known as Cashlandoo (SMR 3:6), a possible raised rath. The total length of the foul sewer was c. 340m, with a corridor originally 10m wide to be stripped of topsoil. However, due to the proximity of the possible raised rath, the working width of the corridor was reduced to c. 4m.

The supervision of the topsoil-stripping revealed several subsoil-cut archaeological deposits within the vicinity of this monument. Seven areas were excavated, only one of which consisted of more than one subsoil-cut feature.

A large prehistoric ditch was located at the north-eastern terminal of the stripped corridor where a pre-existing pumping station was sited. Only one edge of the ditch was uncovered, with the other edge being below the pumping station. The ditch cut across the stripped corridor almost at a right angle, running north–south, but with such a small area exposed it was impossible to tell if it enclosed the Cashlandoo mound, located 12m north-west of the ditch. When excavated, the ditch was found to be fairly shallow, with a maximum depth of no more than 1.3m, while it was over 8m wide to the point where it ran below the pumping station. The base at this point was still flat and showed no signs of rising towards another edge. There were indications that a bank may at one time have existed. When the ditch was excavated, a thick layer of redeposited subsoil was found to be lying directly upon the western edge. This may have been material that had originally been upcast from the ditch to form a bank but that had slumped back. On the base of the ditch a metalled surface, made up of well-laid fist-sized stones, was found to partially survive. Several end scrapers were recovered from just above this surface. Several sherds of pottery, all of which were badly rolled and very fragmentary, were recovered from the ditch. This pottery would appear to be Early Bronze Age in date, but this will only be confirmed by final analysis.

An area of several archaeological deposits was uncovered 20m west of the ditch. This consisted of two linear features, one measuring 0.5m wide and 0.25m (maximum) deep, the other measuring 1.2m wide and 0.25m deep (maximum), both of which ran approximately north–south across the corridor. There were also several small areas of burning found in the area around these two linear features. Although some struck flint was found from features in this area, none of it was a finished ‘tool’ and nothing datable was recovered.

At several other points along the corridor other archaeological features were uncovered. Most of these were shallow pits with no datable finds, although one was an almost circular pit measuring 0.8m across and 0.7m deep. The edges of this pit were heavily burnt, with the normally orange clay subsoil having been burnt red. There was a layer of heavily charcoaled soil near the base, but the pit had been cleaned out and backfilled with brown loam and several large stones. Again, nothing datable was recovered from this pit.

While all of the archaeological deposits uncovered were located close to the Cashlandoo mound, their relationship to the mound remains undetermined. All of the artefacts recovered point to a prehistoric date for the excavated archaeology, while the mound is recorded as being of possible Early Christian date.

All of the archaeology along the route of the fowl sewer was manually excavated and recorded and the construction of the pipe was allowed to proceed.

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