I've wandered and explored a lot of the Cotra area, but I can't get into the Bandit Castle still. I found the Bronze Bandit Key quickly, but it doesn't let me into the castle, which is fine. But I can't find the key that will. I've killed the archers in the front and back of the castle. My tool use is only at level 8, I don't want to get it up to 17 for this door.
Not looking for a spoiler, just a hint to point out what I can't see