In a cave that can be accessed via a ramp that starts at 33.9, 29.7
As you head down into Daggermaw Ravine, Yaga's ledge will be on the right (north) and Mur'og's ledge is on the left (south) past the ogre wayguide. Follow this ledge then head up the cliff at the second wayguide.
You can reach this by jumping from the cliffs to the northwest, or you can climb up from the rocks below. If you try from the cliffs but miss you will take a large amount of fall damage so the rocks are safer (start at 35,24).