Construction and defenses of a castle are very fascinating. Building a castle can take a very long time. Enemies would attack a castle for months so the people in the castle would run out of food. Castles are very damp and cold. Living in a castle could be hard, but they were strong and could last a long time.
Castles have many strong defenses.
Castles and Moats. Kingfisher books, 1994. The World of Castles and Forts. Peter Bedrick Books, 1995. World Book Encyclopedia.2ed., 1993.