Ok, you're right. It's extended on one side and is very well hidden without hugging the wall. Thank you.

I looked several times on that side, but i'll look again. When I fall down, i can see inside the doorway and it looks like there is a guy sitting on a ledge on the opposite side, but I have not seen an opening on the other side yet. I do see ledges that could potentially be hiding an opening from my view, but they are up high so still no idea how to get to them. I'll look around a bit more though.

thanks. It's an item for sure, I looked at it from diff angles and saw it as i was falling. I'll try to make my way to midir and see if I can access that area.

The walls NEVER go away for me, they stay until I teleport outside then walk in.