Place
- Cairowmore, Sligo1
- Caithness-shire, Scotland1
- Callernish, Scotland1
- Camster, Wick1
- Carmac, Brittany1
- Carnac, Bretagne1
- Carnanmore, Antrim1
- Castlewellan, Down1
- Channel Islands, United Kingdom1
- Chysauster, Cornwall1
- Chywoone, Cornwall1
- Châtelandren, France1
- Clontygora, Armagh1
- Coldrum, Kent1
- Cong, Galway1
- Cornwall, England1
- Courconno (?), Brittany1
- Coët-a-Touse, Brittany1
- Craigmadden Castle, Scotland1
- Craigs, Antrim1