A watching brief undertaken on the excavation of foundations for an extension to a cottage to the south of the medieval Abbey on Iona has revealed what appears to be a spread of prehistoric midden material. The watching brief was undertane by Dr Claire Ellis of Argyll Archaeology, under the terms of a condition attached to planning consent by Argyll and Bute Council, on the advice of the West of Scotland Archaeology Service.
The archaeological monitoring revealed a sedimentary sequence indicative of a fairly substantial period of soil/midden accumulation and soil stability in the later prehistoric period. Midden material (including organic matter, ashes, prehistoric pottery, stone tools, burnt and unburnt bone, fire-cracked pebbles and flint flakes and debitage) were incorporated within a compact buried soil. Subsequently, but probably still within the later prehistoric, the land surface on the gentle slope above the site was affected by a period of extreme erosion that affected both the topsoil as well as underlying unconsolidated alluvial/fluvio-glacial deposits (rill and gully erosion). Downslope this resulted in the deposition of a very mixed colluvium (hillwash) on top of the original prehistoric soils. With continued erosion it is possible that some effort was made to trap eroding silt behind make-shift stone revetments.
Previously on this site, it has been reported that a Bronze Age midden was identified during fieldwork conducted by the National Trust for Scotland on the western side of Iona. The identification of prehistoric midden material during monitoring of a small-scale house extension demonstrates that although Iona is famous as an early Christian centre, it is also rich in material relating to prehistoric occupation.