The bottom spine corridor was much smaller than the one above, and rooms only extended off to the left.
We were approaching the main rooms in the bunker.
The shot below shows the same corridor in the 1980s, whilst the bunker was still owned by the Post Office.
They used the upper level, but it seems that they left the lower level alone - it looks like the bunker was
prone to flooding even then.
To put it right would be uneconomical, and the housing association have now installed two pumps to keep
the water level down.