Decorating castles may be a big challenge because of its size. castles interior decor always require luxury design. Choose furniture that will go with a castle theme. You can actually purchase big furniture to adapt rooms size. Curtains can add to the castle theme. Purple, white or pink sheer curtains placed over blinds or behind thicker curtains will help transform modern and luxury atmosphere. Adding chandeliers in the center of different rooms is great for castle design.