I've run through the game a few time now.........that particular door is the secret entrance to the mine. of course, even if you could reach it, it probably wouldn't let you in. another tidbit I've been working on is Willie. he's the real estate guy you run into when crossing bridges and the pass to the fjords. personally, I wish I could run him through, but if you read his mind, he has a hidden stash somewhere around Yup'ik's camp. it's impossible to obtain the dragon beforehand.......this area is poisoned by Damian by the time you evolve. I've been all over this area, but can't seem to pinpoint the location.
when I first played the game, I could have sworn that I found Willie running around on the ledge near where the Goblin enclave is located.........must have been something in the beer