From A Wiki of Ice and Fire
The Dun Fort is a large castle that overlooks the town of Duskendale. The seat of House Rykker, it has a large square keep and big drum towers.
The Dun Fort was the seat of House Darklyn. It was the site of the Defiance of Duskendale, when Lord Denys Darklyn captured and imprisoned King Aerys II Targaryen.
A Feast for Crows
Brienne of Tarth visits the Dun Fort during her search for Sansa Stark. Because Lord Renfred Rykker is with Lord Randyll Tarly at Maidenpool, he left Ser Rufus Leek as the castle's castellan. Brienne also meets the Dun Fort's bald maester, who has a freckled scalp and red mustache.
- ↑ 1.0 1.1 1.2 A Feast for Crows, Chapter 9, Brienne II.