4th cistern

Now I'll accompany you to observe the fourth tank, do you see those pieces of wood stuck there on the wall of the tank? To detach the pieces of tuff more easily, the Greek workers placed these objects, which are called cugnoli, in the cracks of the tuff, wet them and waited for the water, penetrating the wood, to expand it, so it became easier to detach the block of tuff with chisel and hammer. Very clever! Now we salute and leave you in good company.