An ancient stronghold of the First Men on the northern edge of the Neck, raised where the causeway offers the only firm road through the bogs. Twenty towers once crowned a wall of black basalt as high as Winterfell's own. Three stand today, and the wooden keep rotted away a thousand years past.
The Three Towers
The Gatehouse Tower is squat and wide and alone stands straight. The Children's Tower is tall and slender and has lost half its crown, and legend holds that the greenseers called down the hammer of the waters from it and drowned the Neck. The Drunkard's Tower leans where the south and west walls once met. All three command the causeway together, so that any attacker must wade chest deep through black muck and a moat of lizard-lions under fire from the towers he has not yet reached.
The Gate of the North
The Marsh Kings held the Moat against every host that came up out of the south, the Kings of Winter took it from them and kept it, and the Andals broke upon it age after age. It has never been taken from the south. It was never built to face the other way: in A Clash of Kings the ironborn came at it from the west by the Fever River, and in A Dance with Dragons Ramsay Bolton had the surrendered garrison flayed along the causeway.