Iron and Leaves
Oldwall is the remnant of a mighty defensive system that crisscrosses one of the mountain ranges of the north near Dragon Wood. No one is certain who built the wall, or against what enemies. Although often partially buried by avalanches and snow, and battered by barbarians and the forces of the High Druid, the wall is still intact in places. Mapmakers have stopped trying to account for the wall, recognizing that it seems to rebuild itself.
Oldwall can never be mistaken for anything but a ruin of a once mighty fortification, but there’s no way to predict what shape it will be in from year to year and decade to decade. Travelers use it as a rough landmark and occasional shelter. Bandits and monsters use it as shelter. Given that the High Druid has never managed to erase the wall entirely from the wilderness, it may serve her in some way to continue its existence.