The Siege of Macindaw (Ranger's Apprentice)

The pacing felt just right, but I'm curious if that was planned from the start or if it evolved during writing. Did the adventure come first or the characters?

The setting of Macindaw and its surroundings felt very vivid. I wonder how much of it was mapped out beforehand versus developed as the story progressed.

The obstacles felt intense but believable. I'm curious whether these came from historical sieges or purely from the author’s imagination.