Portions of the following information were taken from technicaldiving.ie

A series of sumps beginning at Taff's Well (sump 1) - nine sumps have been dived to a tenth. First dived in 1979 by Martyn Farr. Sump 1 was passed (9 m long at shallow depth) then sump 2 was encountered, and dived for 135 m in poor conditions. In 1983 Farr returned to sump 2, with Campbell and Woods, and passed sump 2 to follow easy walking passage and seven short sumps. He stopped at the tenth sump having run out of line. In 2008 Chris Jewell and Hilary Greaves attempted to regain Farr's limited, but were halted in sump 2 when the old dive line ran into a line trap; attempts to negotiate this failed. In 2009 Jewell again dived sump 2 and bypassed the line trap to regain Farr's line to make some further progress.