The Burren is one of the most famous and unique karst landscapes in Western Europe. The caves in the Burren are unique and have a rich and varied history.
It is an upland area of mostly very pure, well-bedded Carboniferous limestone covering about 400 square kilometres. The longest cave in Ireland is the Poulnagollum/Poll Elva system – currently 16km long, gave its name to Gollum from Lord of the rings.
Doolin lies in the western Burren: Here the hills have summits formed of impermeable shales providing the catchment areas for swallow holes located at the shale/limestone boundary. These caves tend to be wet canyon caves and are liable to sudden flooding.