I honestly still don't know, as after opening that chest that sent me to some mines in Caelid I decided to explore that area and Dragonbarrow and collet their map pieces, as I was just level 16 when that happened and everything there could easily kill, I must say that the only thing I could consider a wall, are those dragons blocking that bridge plus the guys throwing poison through the other route they are walling off my current exploration quest. But well, as I already explore Mistwood, I could say I finished exploring for now. Maybe is time for me to finally visit Stormveil Castle for the first time, then my wall will be either Margit or Godrick. Is level 20 enough to fight them? I will assume that that's not the case.