 An isthmus of swampland named The Neck separates the North from the South.It is home to short, marsh-dwelling crannogmen ruled by House Reed of Greywater Watch, loyal bannermen of House Stark.The Neck's difficult wetland terrain is infested by predatory lizard-lions, restricting the only dryland passage to the causeway commanded by the almost impenetrable stronghold of Moat Cailin, which protected the North from land invasion from the south.