According to local legend, the mountain got its name because the devil took a bite out of it. There is a small gap in the mountain between one outcrop of rock (known as the Rock) and another small plateau. The bite the devil allegedly took made this gap. The legend suggests that the devil broke his teeth taking this bite and the Rock of Cashel fell from his mouth to where it now stands.
The Book of Dimma was supposedly discovered in a cave on the mountain in 1789. It is an illuminated manuscript copy of the four Gospels and was written in the monastery of St Cronan in Roscrea some time during the 8th century. According to legend, Cronan ordered his scribe Dimma to produce the manuscript before sunset on that day. He then used miraculous powers to ensure that the sun did not set for forty days, and Dimma spent all of this period completing the manuscript without feeling the need to eat or sleep. The manuscript disappeared following the dissolution of the monasteries in the 16th century. There is some debate about whether or not the manuscript was actually found on the Devil’s Bit amid claims that it could not have survived without damage in an outdoor environment for over two centuries. The Book of Dimma is currently housed in the library of Trinity College Dublin.
Photo credit: Damien Carroll Photography