Many different trip combinations are possible, most of which involve free diving the 6ft long sump 1. The nearby St Cuthbert's Swallet is 4miles of inclined maze. All the caves in the Priddy area resurge at Wookey Hole. Burrington Combe has many smaller caves including Goatchurch which is popular with novices. South Wales South Wales was the most recent area to attract the attention of cavers.
Limestone occurs at the edge of the coalfields, and some very long cave systems can be found.
Swansea Valley has two well known caves. The system is about twenty miles long, and has a 3 mile long main streamway. Across the valley, Dan yr Ogof has about 10 miles of passage. The caves of Llangatock Mountain have the potential to become the longest cave system in Britain. The three systems of Daren Ciliau, Agen Allwedd and Craig y Ffynnon have a combined length of about 40 miles, and it is only a matter of time before they are connected.