Guide
Geiyo Yosai Kojima is a site of a former military installation located on Kojima Island in Imari City, Ehime Prefecture. It was originally constructed during the Russo-Japanese War to prepare for potential naval attacks. Today, the site serves as a quiet, evocative space where historical ruins—such as artillery positions, observation towers, and red-brick underground bunkers—are seamlessly integrated into the natural landscape. Visitors can experience the intersection of military history and the serene beauty of the Seto Inland Sea.
The history of this site dates back to the Russo-Japanese War era. To guard against the threat of the Russian fleet, significant military infrastructure was developed on Kojima. Historical records indicate that during this period, heavy weaponry was moved between coastal fortifications; notably, two of the six 28cm howitzers sent from this area were utilized in the defense of Port Arthur. This background highlights Kojima's significant role in Japan's modern military history.
The island is dotted with various structures that tell the story of its former military functions. Key features include the remains of artillery positions, an observation tower, and underground barracks constructed with classic red brick. These structures offer a direct look at the engineering and military design of the era. A well-maintained walking path connects these historical points, allowing for a peaceful stroll through the island's past.
While the site is accessible 24 hours a day, it is highly recommended to visit during daylight hours for safety and visibility. A clear, sunny day is best to fully appreciate the contrast between the historic ruins and the calm, blue waters of the Seto Inland Sea. The environment is suitable for observation regardless of the season, though bright sunlight enhances the scenic views.
The primary activity here is "historical exploration." Walking through the artillery sites and underground bunkers provides a tangible way to learn about the structure of past defense systems. Additionally, near Kojima Port, you can see a full-scale replica created for the NHK Special Drama "Saka no Ue no Kumo" (Clouds Above the Hill), offering a unique connection to Japanese literary and cinematic history.
Kojima is located approximately 10 minutes by boat from Hatohama Port. Situated along the popular Shimanami Kaido route, the island is an ideal stop for travelers exploring the Seto Inland Sea via cycling or boat-hopping. It is part of a larger network of islands that blend natural beauty with deep historical roots.
As you will be walking through natural terrain and historical ruins, we strongly recommend wearing sturdy, comfortable walking shoes, as some paths may be uneven or unpaved. There are very limited facilities or shops on the island, so please bring your own water and snacks. Please respect the historical sites and the local environment by following all local manners and avoiding any damage to the structures.