Cluain Carpat: a meadow at the river Cruinn in Cualnge
Cluain maccuNois: Clonmacnoise, on the Shannon, about nine miles below Athlone
Cnoc Aine: Knockany, a hill and plain in the County Limerick
Cnogba: Knowth, on the Boyne, near Drogheda, a couple of miles east of Slane, in the County Meath
Colbtha: the mouth of the Boyne at Drogheda, or some place near the Boyne
Collamair: between Gormanstown and Turvey, in the County Dublin
Coltain: south of Cruachan Ai
Conall: probably Tyrconnel, in the County Donegal
Conall Cernach: one of the chief warriors of Ulster: foster-brother of Cuchulain and next to him in point of prowess
Conalle Murthemni: a level plain in the County Louth, extending from the Cooley Mountains, or Carlingford, to the Boyne