Guide
Tomogashima is a group of uninhabited islands located in Wakayama Prefecture. It was once part of the Yura Fortress, a strategic military installation designed to protect Osaka Bay. Although many structures were damaged by the GHQ after WWII, many artillery sites and ammunition depots remain in remarkably good condition. Today, it is a popular destination for travelers seeking a unique blend of history and nature.
During the late Edo period, Japan faced an urgent need to defend its coasts from foreign naval threats. To protect the entrance to Osaka Bay via the Kitan Strait, the Yura Fortress was developed, connecting Tomogashima, Miyama, and Yura on Awaji Island. At its peak, the fortress housed approximately 600 soldiers. Interestingly, because military power shifted from naval ships to aircraft during WWII, the fortress never actually engaged in combat. Today, the site serves as a fascinating historical monument and a scenic hiking destination.
The island features several artillery sites with different functions. The 3rd and 4th artillery sites were designed as "indirect fire" batteries, positioned on high ground to fire shells based on instructions from observation posts. Other batteries were designed as "direct fire" sites to strike enemy ships passing through the strait.
A standout spot is the ammunition depot at the 3rd Artillery Site, where the interconnected passageways offer a profound sense of history. At the 5th Artillery Site, you can observe the technical details of the era, including steel armored covers and wooden ceilings within the observation posts, providing a glimpse into early 20th-century military engineering.
The ideal seasons are spring (March to May) and autumn (October to November). Since access is via ferry, please be aware that schedules are subject to weather conditions. From December to February, ferries only operate on Saturdays, Sundays, and public holidays, so it is highly recommended to check the schedule in advance.
Exploring the island is a wonderful hiking experience. You can trek through the various artillery sites (1st through 5th) to learn about the defensive systems of the past. The contrast between the weathered concrete structures and the lush natural landscape makes for incredible photography and a sense of discovery.
To reach the island, take the Nankai Electric Railway to Kada Station, then board a ferry from Kada Port. The surrounding Wakayama coastline offers beautiful scenery that highlights the deep connection between Japan's natural landscape and its historical defense systems.
As the island features unpaved paths, stairs, and uneven terrain within the ruins, sturdy walking shoes and comfortable clothing are essential. Always check the ferry schedule before your trip and prioritize safety when walking near the historical structures.