The Round Tower is located on top of a 50 foot, manmade hill or motte. This position is the demarcation between the Upper and Lower Wards. This is why it is often called the Middle Ward. The constable, who heads the garrison in charge of defending the castle, lived in the upper floor apartments. Historically, this role included being governor and head of the court. Inside of this keep are several rooms including a guard chamber and dining room. The Round Tower dates back to the 12th century. An additional 30 feet were added to its height during the early 19th century.