engine room:- (#8 on the layout
by this time mostly everything inside has been stripped bare.
Only a few pipes in the side access tunnels remain. There were
from what I could see 4 air ventilation shafts above ground that
must have connected to this underground area. On the floor inside
the main chamber itself were metal fixing points were I presume
the main engine was fixed.
If you want to explore the interior you'll need a torch and watch
out for all the debris on the ground..