Sumoto Castle Ruins

Sumoto Castle Ruins (洲本城, Sumoto-jō) stand atop Mount Mikuma on Awaji Island, offering one of the island’s most rewarding panoramic viewpoints. From the summit, visitors can enjoy sweeping vistas of the Seto Inland Sea, the cityscape of Sumoto, and, on clear days, even spot Kansai International Airport and the distant Wakayama coastline. Although the original castle was dismantled during the Edo Period, remnants such as moss-covered stone walls, stairways, and lookout terraces still evoke the site’s historic atmosphere. The gentle uphill trail to the ruins winds through quiet woodland, making it a popular route for hikers and those seeking a tranquil escape into nature with stunning views.

Sumoto Castle was originally constructed in 1526 by Atagi Haruoki, a commander serving the Miyoshi clan, and later expanded by Toyotomi Hideyoshi’s generals to secure Osaka Bay from naval threats. While its role in Japanese feudal history was relatively brief, it held strategic importance during periods of regional conflict. At the base of the mountain, the Awajishima Museum displays artifacts related to the castle and local samurai heritage, giving visitors a deeper understanding of Awaji’s historical significance. In 1928, a concrete replica of the main keep was added—the oldest reconstructed keep in Japan—serving as a symbolic monument and scenic observation point rather than a historically accurate restoration.