Irish travel secret: 300-million-year-old Dunmore Cave, Kilkenny
Dramatic calcite formations in Kilkenny are small but perfectly formed in the 300-million-year-old Dunmore Cave, which includes a bat colony and even skeletons encrusted in the limestone. Formed over 300 million years the Dunmore Cave contains some of the most dramatic calcite formations in Ireland.
Source: irishcentral.com