During a mining work in an area near Beni Suef governorate, Upper Egypt, which is mainly characterized by alabaster formation, a huge cave was discovered. A detailed geophysical study, including Vertical Electrical Sounding (VES) and Ground Penetrating Radar (GPR), has been carried out to prepare the area around the discovered cave for touristic activities. During data acquisition another subsurface cavity is discovered. This detection is proved by a GPR profile measured along the inspected cave location. The extension and the depth to the top of the cavity was determined from both Geoelectric and GPR data interpretation. The combination of two different techniques, Geoelectric VESs and GPR profiles, is very helpful in detecting the subsurface features as well as determining their dimensions.