I’ve been reading with interest your Honister & Yew Crag posts. Good to hear some discussion on the old place! In the early 1990's, we spent most of our 'mining' days in there, systematically exploring every inch of the place.
Entered quite a few areas not previously explored by modern explorers.
At Yew Crag, we reopened the 1901 New Level beneath Sam New Quarry, exploring it to a choked rise up into the surface quarry. We also located reopened the Level at the foot of Yew Crag incline (adjacent to the winder control shed), it was previously ‘lost’, buried beneath tons of scree & packwall. We believe that this was the tunnel planned (but never completed) to go through the hill to Newlands to connect with a planned railway up the valley. It’s not shown on the plan in Ian Tyler’s book because we got in just after it went to the printers!!
We’ve been in Dubs bottom level, & the one above (via a small rise) which connected with a square stone lined shaft outside the present hut (now filled in). We think that the 650yd tunnel to connect with Honister was never driven. There’s certainly no sign of it in Honister (I think the Honister Top level or ‘Long’ Level goes the furthest into the hill) we have explored nearly all the Honister levels to foreheads. There used to be some nice sheds with carved names outside Dubs bottom level until Weir smashed them up with his diggers.