From the platform jump down into the water. The first sign is on the wall:
First Sign of Find Something ascociated with Ciri’s horse Kelpie in Wandering in the Dark in Witcher 3 Wild Hunt.
Then dive down to the right of the sign and swim through the cave. Jump up the ledge in the cave ahead:
Jump up the ledge to find the second sign in find something asscociated with Crir’s horse Kelpie in Wandering in the Dark in Witcher Wild Hunt.
The second sign is on a wall further down the cave.
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