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Three Counties System
"The Three Counties System's most southerly entrance is currently Large Pot (54°11′11″N2°29′18″W / 54.186439°N 2.488420°W, NGR SD 6281 7685) on the northerly flank of Kingsdale in North Yorkshire, and the most northerly entrance is currently Bull Pot of the Witches (54°13′35″N2°31′10″W / 54.226398°N 2.519514°W, NGR SD 6623 8131) beneath Barbon Low Fell in Cumbria – a distance of almost 5 kilometres (3 mi). 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."