It has an excellent walk through that tells the story of Sleeping Beauty.
Yes, but it's more of a walk-through with gift shops inside.
Yes
yes. it's a walk through. there are stairs
Yes you can
Short answer: Yes. Long answer: You can always go through the Castle to get from the central plaza of the park to Fantasyland. Usually you can also visit 'Sleeping Beauty Castle Walkthrough'. I say 'usually' because it might be closed for refurbishment, but you should find the closures calendar on the official site.
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