Crun Clach was located in a faerie mound in the lowlands of south west Scotland. It was run by Caitlin Suil Caine, a half-faerie maga of Merinita who was over 300 years old, and possible the most powerful magus in the Order. She, and most of the other magi in the covenant vanished during the Long Day when the faerie regio the covenant was in vanished.
Seumas an Cat ex Miscellanea was slain in 1222 by air elementals that attacked the covenant. He was the last magus at this place. The only other survivor, Caitlin's daughter Aine, has gone to Loch Hourn to finish her apprenticeship.