Far off the the northern coasts, on a wave-wracked island that is little more than a rocky outcropping jutting from the cold sea, are the ancient remnants of a long vanished people.
The hill tribes and meadow clans called them the Briarfolk and thought of them as (and fashioned wooden icons of them as) a hairy and bearded people that could speak with sea birds and woodland creatures. They worshiped at strange standing stones or communed with their mysterious horned goddesses by leaping over bonfires atop hillocks beneath the gibbous or crescent moon.
This map is of a ruined complex left behind by these people, partially built into a cave system on a precipitous near-inaccessible island. Now the island is home only to black-beaked oyster catchers, sea-spry puffins, and the occasional seal colony - or so the locals say, though the keen observer will notice that they never draw too near it on their fishing vessels.