Ridge of Chemary

"Gwaine: Iron ore's pretty rare in Camelot. In fact, I've only seen it once, on a patrol. Merlin: Where ? Gwaine: Er...ridge of Chemary." Alator of Catha abducted Gaius and took him in a cave of the Ridge of Chemary. According to Gwaine, it's the only place in Camelot where we can find iron.