Three Counties System
The Three Counties System is a set of inter-connected limestone solutional cave systems spanning the borders of Cumbria, Lancashire and North Yorkshire in the north of England. The possibility of connecting a number of discrete cave systems in the area to create a single super-system that spans the county borders was first proposed by Dave Brook in 1968, and it was achieved in 2011. The system is currently over long, making it the longest in the UK and the thirtieth longest in the world, and there continues to be scope for considerably extending the system. Description The Three Counties System's most southerly entrance is currently Large Pot (, NGR SD 6821 7685) on the northerly flank of Kingsdale in North Yorkshire, and the most northerly entrance is currently Bull Pot of the Witches (, NGR SD 6623 8131) beneath Barbon Low Fell in Cumbria – a distance of almost . Between the two, the system passes beneath Ireby Fell and Leck Fell which are in Lancashire. The system runs mainly north–south, its western extent being limited by the Craven Fault which truncates the limestone exposure, and the eastern extent where the limestones are conformable overlain by younger rocks. Streams flow