From Zelda Wiki.org
There is a giant stone that seems to have a face that is looking out to sea. Move the stone once you have the
Power Bracelets to reveal a secret cave. In the cave there are a bunch of circular rooms and each of them has a different enemy/enemies, defeat each room and you will see torches light them up, keep on going into the unlit rooms until you reach a room with no enemies. This room is where you play the
Wind's Requiem on the wind mark to obtain a
Triforce Chart.
See Also
Great Sea Islands