Archaeological Prospection in Wetlands—Experiences and Observations from Ground-Penetrating Radar Surveys in Norwegian Bogs

Wetlands are of immense importance for archaeological research due to excellent preservation conditions for organic material. However, the detection and registration of archaeological remains in waterlogged areas, such as peatlands, bogs, mires, or lakeshores are very challenging. Alternative methods that can support traditional archaeological registrations and that can help to survey wetlands more efficiently are needed. One goal of the “Arkeologi på nye veier” (Archaeology on new ways) project, initiated by Nye Veier AS, was to develop and test a practical solution for non-invasive geophysical surveys in wetland environments in support of traditional archaeological investigations. For that purpose, a custom GPR system for wetland investigations was assembled, tested and applied at Gausdal (Flekkefjord municipality, Agder county) in Norway within the E39-southwest infrastructure project. The GPR survey resulted in promising data, clearly showing the buried remains of an old road within the investigated area. This case study demonstrated the potential of GPR measurements in peatlands as a valuable asset for archaeological registration projects in such environments. However, despite these first encouraging results, wetlands remain very challenging environments, and realistic expectations, as well as a good understanding of the potential and limitations of this approach are a prerequisite for meaningful surveys.