Honestly, if you're thinking of getting this book, get "Village Book 1" instead. Most of what is covered in here is covered there, but more in depth. I will be honest, I was tempted to rate 1 star.
If you want a bunch of castle maps then maybe this might be useful for you, but they honestly aren't that detailed.
The only real redeeming feature for me was the "Random Follower Chart" which is interesting, but you probably have a usable table for this already anyway.