Using Ground Penetrating Radar (GPR) to Locate the Remains of the Jaundole (New Dahlen) Castle Near Riga, Latvia

This study investigates the subsurface remains of Jaundole Castle, a 14th-century medieval fortress located on Dole Island near Riga, Latvia. The castle, which has left no visible surface ruins, is known only from historical documents and maps. To assess whether its buried remains could be detected, a non-invasive ground penetrating radar (GPR) survey was carried out across five targeted grids. The results revealed multiple linear and circular anomalies consistent with historical records of the castle’s layout, including possible foundations of walls and towers. These findings demonstrate that GPR, when combined with historical map and image analysis, can effectively locate, and delineate lost architectural features. The integration of historical sources and geophysical data provides a replicable model for the investigation of other completely buried archaeological sites. This work contributes to the development of non-destructive prospection strategies and supports the planning of future archaeological excavations and conservation actions.