The North Grove is a protected area north of the Wall inhabited by the bastard children of Lord Gregor Forrester. The wildlings have heard stories about it, about a "forest within a forest". Gregor Forrester, Josera Snow, Elsera Snow, Duncan Tuttle, Gared Tuttle, Rodrik Forrester, Cotter and Sylvi are the only known men in Westeros so far to know that the North Grove truly exists. Most inhabitants of the North believe it is only a story.
Jon Snow told Gared that the North Grove was mentioned in one of Old Nan's stories. Finn said it's a witch's den where they turn children into giants. Theories say it is just a keep full of Ironwood in case of emergency, whereas other theories say that there is an ice dragon inside. But as it is said, what is in the North Grove is unknown, but it has an important role in the future of House Forrester. The North Grove is also protected by an army of wildling warriors, that are implied to be undead.
A few years prior to Gared's quest to find the North Grove, one of the ice-river clans set out to find it. They had heard stories that the cold couldn't touch it, and that it is safe even in the dark of winter. The clan set out, full of hope, but none of them ever returned. It is implied that this clan became the undead wildling army that protects the North Grove.
- If Royland is named as Ethan's Sentinel, then the player (as Rodrik) has an option to ask Duncan about whether he told Ludd Whitehill about the North Grove during their confrontation on Duncan's treachery in A Nest of Vipers, implying that Rodrik is aware of the North Grove's existence. The extent of his knowledge is unknown.