Excavation
Date 20 August 2018 - 7 September 2018
Event ID 1106252
Category Recording
Type Excavation
Permalink http://canmore.org.uk/event/1106252
ND 3210 4573 Investigation this season, 20 August – 7 September 2018, extended the area of the previous excavation to the E and S, in order to further investigate the well preserved structural features defined during the 2017 excavation season (DES 18, 132). The excavation area in 2018 season consisted of an area 10m long SE/NW by 10m wide SW/NE. A 5 x 2.5m wide extension was excavated to the S of the main trench area.
The work aimed to define the extent of the structural features in relation to the earth resistance survey, establish the stratigraphic and chronological relationships of the structural features, and investigate the potential for preservation of in situ deposits.
This season of excavations identified that the earliest phase of activity on the site is likely to be a series of structural features truncated by the erosion at the edge of the Burn of Swartigill. Radiocarbon dating from deposits associated with these structures in previous seasons of excavation returned an early to middle Iron Age date (366 – 192BC).
The structures eroding from the burn section include a small cist feature, measuring 1.2m long by 0.6m wide and 0.45m deep. The cist had been partially destroyed on its N side by erosion of the burn bank. Despite the apparent damage to the feature, the lower deposits within the cist appeared secure and were sampled for analysis.
The structural remains within the eroding burn section were overlain by an ash rich deposit, which was in turn truncated by the construction cut for a revetment wall for a passage structure to the S.
Structure A represents a curvilinear passage building, which extended 10m across the full width of the excavated area on a SW/NE alignment on the W side of the trench and turning to the E. The passage was defined by a northern revetment wall on the N side with a curvilinear arrangement of boulders forming the southern wall. The passage measured between 0.7m wide at its narrowest point at the W end, and 1.9m wide to the E. The interior of the structure features a threshold stone at its W end, with a flagstone surface throughout the building. The flagstones formed the capping for a substantial drain running through the E/W portion of the passage, which gradually slopes to the E, where it widened into a sub-rectangular chamber.
Structure A was infilled by collapsed structural material and disorganised rubble deposits. Radiocarbon dates from deposits sealing the rubble infill of this structure collected in previous seasons of excavation returned a date of 198-47BC. The full extent of this structure extended beyond the E and W edges of the current excavation area.
Structure B was situated directly to the S of Structure A and was abutted by the rubble core of the southern boulder revetment of Structure A. Structure B consisted of a sub-oval structure with an internal area measuring 6m wide N/S by 7.5m long E/W.
The structure was defined by double-faced walls, with an entrance aperture on its E side. A possible hearth setting was identified within the centre of the structure, defined by an area of carbon rich ashy deposit within a circular stone setting. Further possible occupation deposits were identified in the interior of the W side of the structure. The interior of the structure is partially infilled by rubble material, which is in turn overlain by peaty deposits and alluvium.
Evidence for a third well-preserved structure was identified in an extension of the trench to the S of Structure B. Structure C was defined by an arrangement of edge set stones, at right angles to each other, forming the interior face of a chamber, backed by coursed masonry and rubble. Only a small portion of this structure was identified within the excavation area, with traces of a portion of the structure continuing to the W with a passageway between Structures B’s south wall and Structure C.
A significant assemblage of artefacts was recovered during this season of excavation, mainly comprised of prehistoric pottery. The majority of the pottery sherds were found in deposits within the eroding burn section. A number of hammer stones were also recovered from contexts across the site. A fragment of shale bangle with a D-shaped profile was recovered from a rubble deposit in close proximity to the eroding burn section.
Archive: NRHE
Funder: Yarrows Heritage Trust, E.ON, Eneco UK, Lybster and Tannach, Foundation Scotland, and Caithness Archaeological Trust
Rick Barton – Orkney Research Centre for Archaeology (ORCA)
(Source: DES Volume 19)
