Kaer Carreg or Karreg is the seat of Lord Harald, and perches on a natural promontory that is slightly separated from the island and reached via a bridge. Kaer Carreg is a wood and stone 'castle', consisting of a stone tower and several buildings that house Harald, his family and household.
Kaer Carreg is functional, housing the household, a kitchen, a great hall and a small armoury. Living quarters are sparse: Harald has a small study/library attached to his quarters (shared with his wife Gisla), whilst Astrid, Sven and Ragnar have rooms of their own. The rest of the household sleep within a curtained area of the Great Hall.
- Name of the castle is in Skellige jargon of Elder Speech and means presumably "Stone Keep".
- In the real world, Caer Garreg is Welsh and means "Stonecastle" or "Fort of Stone" (Caer meaning castle or fortification and carreg meaning stone or rock). Kaer/Kêr Karreg means "City of Rock/Stone" in Breton.