The “Otemon Gate” of Osaka Castle is the main entrance to Osaka Castle and is located on the west side of the castle. This gate has historically played an important role as the main entrance to Osaka Castle. The name “Otemon” generally refers to the main gate of the castle and is considered one of the most important parts of the castle's defense. The present Ote-mon Gate, restored in 1931, is a symbolic structure that conveys the grandeur of Osaka Castle from the Azuchi-Momoyama period through the Edo period. The gate is a wooden structure built on a sturdy stone foundation, and its solid construction is designed to prevent enemies from entering. Large stone walls were placed around the gate to provide a strong defense against an invading enemy. The history of the Otemon Gate is deeply connected to the history of Osaka Castle. The original Osaka Castle was built by Toyotomi Hideyoshi in 1583, but was later destroyed by fire by Tokugawa Ieyasu during the Osaka Summer Battle of 1615. It was then rebuilt by the Tokugawa Shogunate in the Edo period, but was damaged again in the Boshin War of 1868. In the Meiji period, a part of Osaka Castle was used as a military facility, and Otemon Gate became a part of it. The current Otemon was restored in the early Showa period (early 20th century), and was reproduced as close as possible to its original form using the construction techniques of the time.