Local landscape transformation at the Hedeby-brook valley in the Viking proto-town Hedeby

Abstract

Viking proto-town Hedeby located in Northern Germany belongs to the archaeologically most intensively investigated Viking Age sites. Nevertheless, there is only very scarce information about landscape transformation in Hedeby during the Viking Age. This geoarchaeological research, which included coring transects, geochemical and micromorphological analyses as well as radiocarbon dating, revealed that inhabitants of Hedeby intentionally altered the landscape in the settlement to a much larger extent than thought before. A large buried valley-like feature was discovered in the western part of the settlement following the course of the Hedeby-brook, which represented an important element of the settlement landscape. Based on the estimated dimensions of the valley-like feature, its volume equalling at least 10,000 cubic meters was calculated. A number of considerations allowed excluding natural origin of this feature and suggested human activity to be responsible for its formation. Moreover, it was concluded that the valley-like feature was excavated during the settlement period in the Viking age. Possible reasons for the formation of the valley-like feature were discussed in detail with main hypotheses being material extraction for the construction of the semi-circular rampart and water management in the settlement. Regardless of the initial goal for the formation of the valley-like feature, it started to fill with various material already during the settlement period. On the one hand, waste material originating from neighbouring households and workshops was disposed there. On the other hand, natural sedimentation due to soil erosion from the neighbouring slopes took place there. The end of the settlement period was clearly marked in the stratigraphy by the onset of peat formation followed by a new phase of colluvium deposition triggered by agricultural land use in medieval and modern times. The valley-like feature was part of a large landscape engineering project in Hedeby and it undoubtedly played a major role in the organization and functioning of the proto-town at least in the early settlement phase.