To determine the date of the main collapse inside the Shisur cavern, excavations were initiated just below the latest overhang. Three m. square excavations below and inside the overhang, proceeded down at least four meters in sandy blown-in soil mixed with animal dung. Squares outside the overhang, were excavated to three m. depth. Further work was impeded by the collapse of large boulders at some time in the past. Ground penetrating radar (GPR) passes over the area suggested a major interface at seven m. below the current surface.