To support their learning of Physical Geography the 5th and 6th Year Geography students delved down into the subterranean world of the Mitchelstown caves, Tipperary. They enjoyed exploring a kilometre of cavern networks beneath the surface; observing the slow growth of stalactites, stalagmites and pillars; and learning about the history of their excavation. The students were also amazed to see a seismometer in the caves and to learn that even their footprints could alert seismologists in Dublin. The highlight of the tour involved experiencing complete darkness (momentarily) and seeing the process of carbonation under UV lights, which glowed an eerily blue light within the caves.