6th January 2013. A while ago I noticed a small rift in Harptree Combe near to the aquaduct (NGR ST 5618/5598).
Entrance is ~1 metre x 0.7 metre, rift is ~3 metres deep. In dolomitic conglomerate and is probably formed along a slip joint, there appears to be a very small continuation at the base of the rift. There are no obvious signs of mining activity.