When the devil was banished from Ireland by St. Patrick, he left his mark at this mountain: from the cache site you have a great view of the gap where he has bitten into the rock. He broke one of his teeth, spit it out, and it became the Rock of Cashel.
A large cross across the gap was erected in the Marian Year 1954. See Wikipedia for more local history and information.
The easiest access to the mountain is from south: there is a parking available at the trailhead of Devil's Bit Loop Walk. An alternative approach is to climb Killduff Mountain - the relay transmitter site - from the east and walk the ridge to the trigpoint.
The nearest public transportation is Templemore train station. The bus stop at Moneygall seems to be close enough but there is no trail leading up from the west, the slopes are steep and overgrown with gorse and brambles.
The cache is a small plastic screw-top container. Enjoy!