Until now we have excavated in the tunnel in the area indicated as "Photo A" bellow, and now on the other side of the wall we found an aperture like a drain indicated as "Photo B".
But we are uncertain how functioned that tunnel yet,
and the excavation in this year will be closed soon.
We found that an architectural element along the wall is a kind of a tunnel that leads to "Area 12". We have removed all the soil filled in it. And now you can see the trace that shows a water pipes were pulled out on the floor.
We dug in the hole, and found a small tunnel below. It may be a kind of channel.. But it is still unknown where this channel comes from, where that leads to and how that worked.
During the removing the soil before the eruption of 472 A.D. we found an
architectural element along the wall. it is united with the wall. But
it doesn't seem to be a normal foundation of a wall formed in the earth.