The history of exploration of the caves of Casterton and Leck Fell is complex and goes back to records from the end of the 19th Century. Below are links to a selection of articles produced by Red Rose members. For full list see link to Club Publications page.
Another useful
set of references is on the Northern Pennine Club's website The
earliest publication of which knowledge still persists is
"Caverns of Upper Easegill", published in March 1952 as a 'Northern Pennine Club
Publication', and reprinted (on paper) in 1987 and compiled by
A.Jowett,B.Sc.,Ph.D. & J.Aspin,M.A.,M.D. There are many other
references on tis site to Ease Gill Caverns explorations by that club
and RRCPC members e.g. Connection of Easegill Caverns to Lancaster
Hole via Poetic Justice by Bliss et
al.