Not much remains of Sna Broch these days, years of storms and coastal erosion have reduced the main broch to nonexistence though the outer ramparts and ditches remain. It was to these we turned our attention in September for a clean and record under the leadership of the SCAPE Trust and with much help from the community of Fetlar.
Despite the absence of the broch itself, what remains is invaluable. Much of this is because we have a visible cross-section of the defensive structures giving us a glimpse into how they were constructed. This is rare indeed and reminiscent of the opportunity we had at Channerwick Broch where erosion had also revealed a cross-section, the broch itself and a later wheelhouse, which was another site where we had the opportunity to help the SCAPE Trust.
Another benefit to the erosion is it reveals possible dating material. For example, several potsherds were found along with hammerstones, the former giving some potential context. A well-preserved piece of wood and waterlogged deposits accumulated at the base of the ditch provide an opportunity for more precise dating for the construction of the defensive structures.
Another interesting aspect is the chance to get some dates on ramparts and ditches themselves. Many brochs in Shetland show no evidence of defensive structures such as these. If more dates from other sites are added to the record, we could determine whether or not they were constructed during a narrow timeframe as a response to…something. Even if the dates are more diffuse, it has interpretive benefit to compare and contrast those with and those without ramparts and ditches.
And speaking of response to…something, during the 18th and 19th centuries it was speculated to be a Roman Fort by George Low and Samuel Hibbert, respectively. Much of this was an imaginative sketch of what was missing due to the erosion of the structures and its protection of a supposed well which was believed a typical model of Roman fortlet construction.
For some interesting aspects, we strongly suggest looking at the Sna Broch 3D model developed by Hamish Fenton.