From Llethrid Bridge on the B4271, follow the track South to Green Cwm for about 50 metres. The entrance is in the East cliff and is on Forestry Commission Land. The cave is gated.
See caving.wales for current Access arrangements
Description
The cave is liable to severe flooding. A 5 metre pitch leads to the first chamber from which a crawl of 260 metres leads to the stream passage (normally dry), which is about 830 metres long. The top sump has been dived, but chokes with gravel after 28 metres. The bottom sump dries out in dry weather giving access to several hundred feet of passage ending in an impenetrable sump.