what's with the learning tree?

OK, I might just be dumb, but for some reason, when I try to enter the spot on the map labeled Entrance to the Learning Tree, all I see is a picture of what looks like a big rock with cracks in it and some text that reads, "The Learning Tree." If I click on the text, I just go back to where I was. Do I have to complete a certain quest to be able to access the Learning Tree?

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That's not the Learning Tree, that's the Learning Tree entrance to the hidden Garendall tunnel system. The Learning Tree is an actual tree with 3 people standing outside. You'll know when you find it.

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GameRanger SN: Col. Patrick (EL)