Located in the rolling green of the Tipperary countryside,the Devil’s Bit is a gap between a plateau and an outcrop of rocks. The top of the mountain looks as if a chunk has been taken out of it, which local folklore has explained as a result of the Devil biting into the mountaintop.As the epic goes, or the Devil broke his tooth during the bite and spat it out,forming the Rock of Cashel outcrop, a historic landmark about 20 miles to the south. (A fun epic, and even if the Devil's Bit Mountain is comprised of sandstone while the Rock of Cashel is limestone.)In reality,the curious bite-shaped gap is a geological anomaly, but this region is surrounded by myth. It has also been said that the Book of Dimma, and an 8th-century manuscript copy of the four Gospels of the Bible,was discovered near the Devil’s Bit in 1789. There is some debate on whether the manuscript could fill survived in the conditions it was rumored to be discovered in, but the supposed discovery highlights the intrigue surrounding the mountain.
Source: atlasobscura.com