If we all agreed on what something was or wasn't then there would be no need for a discussion Philip
Whatever people assume underground sections to be isn't the main issue, it is the fact that they have been found and recorded is good enough in my book.
I wouldn't touch the Williamson's Tunnels theory of 'are they tunnels or roads' as you have to define what a road actually is. Certainly there is documentation of two horse drawn carriages passing side by side in an entrance to the Williamsons Tunnels!
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