Topographical survey and analysis by GPR for the structure recently found in Ravne Labyrinth

During the research for a structure had buried for centuries, a proper study is necessary to limit the excavation area and the possibility of damaging the structure with mishandling. In the case of Ravne’s tunnel proceeding to remove the earth that filled them, we realized that this solution could be conceived by the builders or by those after them to protect and hide better something placed below the current floor or inside the walls. For this study we started to study the whole system of tunnels looking to find out a possible abnormality in the levels and shape of the galleries from the architectural point of view, but also we have begun to look for the presence of something under the floor with the GPR (georadar) . We therefore used a GPR model Detector Duo IDS (Pisa – Italy) with new dual wide-band frequency antenna at 250 MHz and 700 MHz for geological features that can reach 5 meters deep in the survey, even in difficult wet conditions, able to obtain high resolution reliable images. In this way we have identified an anomaly at about 90 meters from the entrance whom we represent in this article in its features and even through this study may be more easily brought to light.