ABSTRACTThe present work shows some results of an early ground‐penetrating radar (GPR) study performed in a hazardous karstic area near the village of Nociglia in the central part of the Salento peninsula (Apulia, southern Italy), after a sudden subsidence event occurred on March 13th, 1996. The geophysical study, also involving vertical electric sounding (VES) and refraction seismics, is part of a multidisciplinary research project, aimed at determining the climatic, geological, morphological and hydrogeological conditions of the area in order to assess geological hazards and to prevent groundwater pollution due to agricultural activities. GPR transects led to the identification of some shallow subsurface structures including a known cave and probable karstified bedding joints, weakened shallow layers, fractures, fault zones, and burrows. The VES and seismic surveys resulted in a better understanding of the geology of the area and supported the interpretation of the GPR data.