1999:653 - CASTLEGAR, Mayo

A rescue excavation was carried out at Castlegar, Claremorris, on behalf of Mayo County Council before road construction for the Knock–Claremorris Bypass. The excavation site, a recorded monument, is classified as an enclosure. Before excavation an inner bank and outer ditch were seen to delimit the site. The ditch was shallow, and the bank had been reduced to a scarp except for a short distance at the south-west.

Quarrying had removed sections of the enclosing bank, and a relatively large area of quarrying had occurred at the north and the south. The enclosing element had been reused, since the 1848 OS 6-inch edition, as a field boundary. A magnetic gradiometry survey also revealed the remains of ridge and furrow cultivation overlying the entire site.

The chamber of a souterrain, built of drystone walling, is in the south-west quadrant of the interior.

The enclosure encompasses the apex of a small hillock, and in order to facilitate the road-cut a section through the western edge of the hillock was to be removed. A rectangular area 60m x 30m corresponding to the outer limits of the site was excavated before its removal by the road development. This corresponded to the outer edge of the enclosure on the western side and a small section of the interior.

The excavation revealed a widely splayed V-shaped fosse, cut into the gravel hillock, defining the outer edge of the enclosure. The fosse averaged 1.8m wide at the upper levels, tapering to 0.3m at the base. It reached a maximum depth of 2m. The ditch was backfilled in three stages. The upper fill appeared to be modern, while the layers below appeared to have been a deliberate backfill, perhaps in antiquity. Sandy clay at the base of the ditch indicated that it had been open for some time before the primary ditch fill.

There was no evidence found during the excavation for an internal bank. Along the northern edge of the site the bank had been removed by quarrying. Elsewhere in the excavation the bank is likely to have been levelled during the construction of tillage ridges that were seen to cover the excavation area once the sod had been removed.

A subcircular pit averaging 1.3m in diameter and 1.2m deep was revealed 15m west of the enclosing ditch, on the outer edge of the excavation area. There were no finds within the pit fill to indicate a probable date or function, and it may have been an extraction pit. There were no other features outside the line of the ditch, and natural gravel was reached quickly in this area once the topsoil had been removed.

Limited excavation of the interior revealed the remains of a creep and a second souterrain chamber extending at a lower level in a north-east direction. A narrow cobbled pathway was also uncovered leading towards the creep. The souterrain chamber and the area around it were backfilled, and the features within the interior were not fully resolved.

The finds were blue glass beads, a fragment of a decorated glass bracelet, whet stones and a bone knife handle. The broken base of a rotary quern and a holed stone, which may be a loom weight, were also uncovered. Animal bone was found within sealed contexts of the ditch fill. Worked chert was found in the topsoil, and clay pipe stems and modern pottery were found in association with the disturbed areas of quarrying.

1 Chapel Lane, Killala, Co. Mayo