Interventions were confined to those positions where the residual load-bearing capacity proved inadequate, or where the type of damage threatened the construction’s stability. These involved the antechamber vault and longitudinal walls. Where it was necessary to achieve a reliable static function in restoring the continuation of the cracked stone blocks, this was done with grouting and onsite bonding. This solution was chosen to avoid dismantling the antechamber vault, which by virtue of the condition of its stone blocks would have led to a significant loss of authentic material. The bonds are stainless steel high-adhesion rods which will be inserted into bored holes and incorporated using an injectable compatible mortar of special composition. The main goal was to preserve the structural autonomy of the stone blocks following the application of the grout. The composition of mortars for this intervention was based on the physicochemical and mechanical properties of the stones and was studied by the Laboratory of Building Materials of Aristotle University of Thessaloniki’s Civil Engineering Department (under the scientific supervision of Professor Ioanna Papagianni).