"Digging around" excuse the pun - there appears to be 9 recorded shafts or drifts, and probably more on the 54 acre site.
Or so says this (old?) Whittle Colliery sales piece:
Knight Frank pdf
found some online pics of what I assume is the old drift?
http://alnwickphotos.blogspot.com/20...umberland.html
curious, never seen those before.
On the old 1923 OS map there are shown two drifts in close proximity to each other.