Beyond the Walls: The Pale
The dead lands where the threats gather. (Creative interpretation.)
Canon status: creative interpretation. The app card names no lands beyond Veyrhold.
What the Pale is
The Pale is everything the wall-lanterns cannot reach: a belt of dead forest, ash fields, and ruined hamlets ringing Veyrhold on three sides. (The fourth side is cliffs, and the Ward thanks the cliffs daily.) Nothing grows there that the Ward would eat. The threats of the Bestiary den there, and the Ward's doctrine is never to pursue beyond the treeline.
Why the Ward doesn't cleanse it
Three Black Wardens have tried. The first died there. The second came back Hollow. The third — the Ward's chronicle is tactful — "redrew the maps instead." The Pale does not stay cleansed; it refills, the way a wound refills with blood. So the Ward holds the walls, keeps the lanterns, and lets the Pale be the Pale.
The treeline rule
No warden crosses the treeline alone. No patrol crosses it after moon's height. Nyra Veyl has crossed it alone twice, by the Ward's count. The Ward does not ask about either time.