Note: This item is currently in the 'Proposed Content' section
The Wookey Hole Caves are a series of limestone caves in the village of Wookey Hole on the southern edge of the Mendip Hills in Somerset, England.
The full extent of the cave system is still unknown with approximately 4,000 metres (13,000 ft), including 25 chambers, having been explored.
Editor's note: This item is suggested not for inclusion, because the same could be said for a great many cave systems. It also probably falls under the 'Coastline Measuring Problem' - that's to say there can never be a 'final' measurement.