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 86 kilometres (53 mi) 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.
Duke Street in Ireby Fell Cavern II
Wilf Taylor's Passage, Lancaster Hole
A caver descending a 25-metre (82 ft) shaft in Notts Pot
Calcite formations in Witches II cave.
Short Drop Cave - Gavel Pot System
Short Drop Cave and Gavel Pot are different entrances into the same cave system on Leck Fell, in Lancashire, England. The main top entrance, Short Drop Cave, is a small hole in a fenced off shakehole near the main stream sink. Gavel Pot, a window into the system, is a large fenced shakehole some 40-metre (130 ft) deep requiring tackle to descend. There are two other smaller entrances into Short Drop Cave. At its base the system links via a sump with Lost Johns' Cave, and is part of the Three Counties System, an 87 kilometres (54 mi) cave system which spans the borders of Cumbria, Lancashire, and North Yorkshire.
Calcite formations in Glasfurd's Chamber