Innoshima Suigun Castle

Innoshima Suigun Castle is a modern castle structure on a hilltop of Innoshima Island with exhibits focused on naval history of the Seto Inland Sea region. The white building houses artifacts, documents, and information about maritime activities that shaped the area over centuries.

The building was constructed in 1983 and commemorates the former base of the Murakami, a sea warrior dynasty who controlled maritime trade routes during the Muromachi Period. This family played a significant role in regional history through their dominance over sea passages.

The museum displays traditional weapons and armor that document the seafaring tradition of the Murakami family across several centuries. The exhibits give a sense of how these sea warriors organized their power and maintained control over maritime routes.

The museum is accessible from the mainland by bus across the bridge that leads to the island. The nearest stop is near the port, from where you walk uphill to reach the castle.

From the observation platform, you can spot ten strategic points where the Murakami once positioned fortifications to monitor shipping traffic. These locations demonstrate how the family distributed their presence across the entire region.