Isle of Faces
From A Wiki of Ice and Fire
The Isle of Faces is a sacred island in the middle of the lake called the Gods Eye, located in the southeastern Riverlands. It is one of the few known locations of weirwoods in the south of Westeros, the others having been cut down and burned. 
- See also: Images of Isle of Faces
At the end of the Dawn Age, following many centuries of fighting between them, this island is where the First Men and the children of the forest signed the Pact ending their wars against each other. In celebration, every weirwood on the island was given a face, so that the gods would witness the pact. 
A Storm of Swords
Meera Reed tells Bran Stark a story about a crannogmen who went to the Isle of Faces in the year of the false spring. He remained there for a while before travelling to a tourney in which the Knight of the Laughing Tree participated.
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