The ruins of the Wakitoraguchinomon Gate in Matsue Castle are known as part of an important structure that served as the castle's defense and entry/exit point. This gate ruin was one of the routes leading to the main gate and the castle grounds, and was especially designed to prevent the entry of enemies. The name “Wakitoraguchi” refers to the side entrances and exits, as opposed to the main entrances to the castle, such as Otemon and Uramon. This served to prepare for attacks outside the main route during sieges. Historically, Matsue Castle was built around 1611, and this gate is thought to have been installed at the same time. The castle structure at that time emphasized rationality in attack and defense, and the “Waki-toraguchi-no-Mon” gate is a symbolic example of this. Today, the “Waki Toraguchi-no-Mon ruins” retain their appearance as stone walls and other remains, and are an important place that gives visitors a sense of the design philosophy of the castle at that time. Although the gate itself does not remain, the layout and shape of the stonewalls provide clues to the architectural techniques and defensive strategies of the time. The ruins of the gate also help to enhance the historical value of Matsue Castle as a whole, attracting the attention of castle researchers and tourists.