For most of my life, I would have kept it. But now... the world's not the same and I'm afraid I'd be jumping and looking over my shoulder at every little noise. I'd have to sell... maybe buy another cabin a little closer to civilization.
I like the idea of the cabin. However, there's no driveway, and having to haul everything from God knows where across that rickety bridge, plus the prospect of getting snowed in in a remote spot and then having to dig my way out, is not enticing. So I would sell it.
I would keep it depending on the area it was in if I didn't have to deal certain on going nature issues like fires, as @bobcat mentioned. As far as getting there, the bridge can be updated as well as the driveway.
I would much rather have a musty old cabin than a second home with all of the modern conveniences.
There is something comforting, for me, about the simple rhythm of life and basic chores in a cabin as opposed to the more demanding housework associated with living in a proper house.
I would keep it and sell my house. I think of the peace and quiet. If it needed a drive way or something, I could use from the proceeds of selling my house to take care of that.
It depends. If I had someone staying there with me, I would keep it. It looks so quiet and serene. Me being by myself, I would sell it. I'd freak out living in the woods by myself.