The Drowning of a Cornish Prehistoric Landscape : Tradition, Deposition and Social Responses to Sea Level Rise

Abstract
A Bronze Age barrow excavation north of Penzance undertaken in 2018, and the coring of Marazion Marsh, a RSPB reserve in 2019, are presented in this volume. They provide a platform for discussion as to the implications of loss of land for prehistoric communities. This went beyond the loss of land for settlements, buildings and pits, but extended to the loss of pasture and farmland, and to the salinisation of freshwater. These necessitated changes in the whole economic base of coastal communities if they were stay exploiting the same, but changing, landscape.
Nestling above Penzance, the Middle Bronze Age barrow overlooked a locally perched wetland, with moorland beyond. Finds from the barrow included an important almost pure copper Late Bronze Age ingot. In contrast, in the shadow of St Michael's Mount, the reed bed at Marazion Marsh is separated from the coast by a shingle bar and small sand dune system. This is Cornwall's largest reed bed, beneath which is a 9-m-deep peat and sediment sequence recording nearly 10,000 years of landscape and land-use change from the Mesolithic to the medieval period. Both sites lie within an area of coastal hinterland, which has been subject to incursions by rising sea levels. Since the Mesolithic, an area of approximately 1 km in extent between the current shoreline and St Michael’s Mount has been lost to gradually rising sea levels. Given their proximity, the opportunity was taken to draw the results from the two projects together, along with all available existing palaeo-environmental data from the Mount’s Bay area, presented in one place for the first time. Evidence for coastal change and sea level rise is discussed and a model for the drowning of the landscape presented. In addition to modelling the loss of land and describing the environment over time, social responses including the wider context of the Bronze Age barrow and later Bronze Age metalwork deposition in the Mount’s Bay environs are considered. The effects of the gradual loss of land are discussed in terms of how change is perceived, its effects on community resilience, and the construction of social memory and narratives of place. The volume demonstrates the long-term effects of climate change and rising sea levels, and peoples’ responses to these over time.