The walls will be thick -- and yes, in the forest. [ Once the bandersnatch grows up, she imagines it will help defend it simply because it's home, but she isn't going to base all her home defense on a bear-thing, either. ]

It'll be made of stone, since that's what we have to work with, and the workers can put magic into them -- apparently. [ She'll be testing that, too. ]

The sort of manor I'm building is like a castle itself, only much smaller.