The huge rock from which Carrigtwohill derives its name is about half a mile north-eastwards of the town itself, and is in the townland of Carrigane. The rock is honeycombed with caves; some are large and extend for miles underground where stalactites are to be found. Tradition has it that a goat once entered one of these caves, emerging in the townland of Ballintubrid, a few miles southwards. The cave where the goat emerged is called "Poll an Ghabhair", meaning The Goat's Hole.