EHG5375 - Excavation - proposed new substation site, Connagill

Full excavation of a prehistoric roundhouse on the site of an access road to a proposed new substation at Connagill, Sutherland was undertaken by C Dagg between 24/02/2014 and 18/04/2014. The feature had previously been subject to trial trenching (see EHG5374) to confirm its identification and establish the survival of archaeological deposits. As local topography prevented flexibility in the design of this road, and after consultation with the client, SSE, and Highland Council, it was decided, in order to minimise delays to the developments on site, to investigate and record the features through total excavation. This gave a total initial excavation area of 11.5m E-W by 13m N-S, with the four quadrants being separated by offset baulks 0.5m in width. A fifth trench was opened to the west of quadrant 3, separated by a baulk of 0.5m and measuring 2mx2m, at points 11.5-13.5m E-W and 5-7m N-S In week 6 all baulks were removed manually. A mechanical excavator was used to strip topsoil to extend the open area by 4m south, to 17m, and by 2m west, to 13.5m, as well as stripping the area of the proposed access road approaching the site from the SW, although this area proved to be archaeologically sterile. After full recording, sections through the structure wall were removed; a narrow section through the NW quadrant and a broader section through the east quadrant. The latter was assisted by the use of a small mechanical excavator to lift the larger stones out of the trench without damaging the trench edges. Excavation revealed a substantial structure of at least 3 distinct phases of occupation during the prehistoric period, and re-use probably during the early Modern period. During excavations sediment, charcoal and burnt bone samples and small finds consisting of ceramics and stone tools were recovered. A more detailed study following results of post-excavation analysis of artefacts and environmental samples and return of C14 dates was intended to be produced. <1> NOTE: There is no plan in the report which puts the excavated area onto an OS map grid so the location and GIS extent is assumed from the dimensions given.