Castle Cerwyn, also known as Cerwyn, is a castle in the North, located south of Winterfell, along the Kingsroad and miles north of Moat Cailin. It is the seat of House Cerwyn, vassals of House Stark.
Roose Bolton sends his recently legitimized bastard son Ramsay to Cerwyn to collect taxes from his new vassals. Lord Medger Cerwyn, however, refuses to pay; proudly professing his loyalty to House Stark, and denouncing Bolton as a turncloak. For his defiance, Ramsay has Medger flayed alive, along with his wife, and brother while forcing Medger's son to watch the ordeal. When Ramsay relays these events to his father he casually remarks that the new Lord Cerwyn paid his taxes.
As they advance on Winterfell, Sansa Stark insists to Jon Snow that their small army needs to ride ahead to Castle Cerwyn to try to recruit more soldiers, but Jon says they've run out of time and have to attack immediately.
In the books
In the A Song of Ice and Fire novels, Castle Cerwyn is the seat of House Cerwyn, loyal bannermen to the Starks.
Bear Island · Last Hearth · Karhold · Dreadfort · Winterfell (Winter town) · Deepwood Motte · Torrhen's Square · Castle Cerwyn · Hornwood · Ramsgate · Widow's Watch · Barrowton · White Harbor · Oldcastle · Moat Cailin · Flint's Finger · Greywater Watch · Rillwater Crossing · Ironrath · Highpoint
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