Guide
The Osaka Castle Stone Quarry Site is a quarry located on Shodoshima Island, Kagawa Prefecture, where stone for the walls of Osaka Castle was once extracted. The area known as the "Tengu-iwa Quarry Site" is particularly famous for its massive granite rock, standing 7 meters high with a circumference of 35 meters. This giant stone visually demonstrates the immense scale of the quarrying operations that once took place here. The history of stone culture lives on quietly amidst the natural beauty of Shodoshima.
The history of this site dates back to the construction of Osaka Castle by Toyotomi Hideyoshi and its subsequent reconstruction by the Tokugawa Shogunate. Initially, stones for the castle's walls were sourced from regions like Ikoma and Rokko, but to facilitate maritime transport, the quarrying sites shifted to the islands of the Seto Inland Sea. These quarry sites, including the Tengu-iwa area, are believed to have been opened by the Chikuzen Kuroda Clan. Records from 1621 (Genna 7) indicate that quarrying began with the permission of Kobori Enshu, who governed Shodoshima at the time. The extracted stones were used in critical construction phases, such as the second stage of the Honmaru (main keep) construction.
The primary focus is the overwhelming presence of "Tengu-iwa." This massive granite block showcases both the beauty of natural formation and the history of human quarrying technology. A total of 1,612 stones have been identified in the surrounding area, suggesting this was one of the largest quarry sites on the island. You can observe 38 different types of markings (engravings) on the stones, some of which are the same types used in the walls of Osaka Castle. These markings are vital clues for identifying which stones were transported to where. Other nearby quarry sites, such as Tofu-ishi, Kamezaki, Minami-ya, and Hachinin-ishi, each offer different historical perspectives.
As this is an outdoor site located in a natural environment, the scenery changes with the seasons. On clear, sunny days, the texture of the massive rock and the intricate markings are easiest to observe. The harmony between the historical ruins and the surrounding nature offers a different atmosphere each season. Since there is no lighting equipment, visiting during daylight hours is highly recommended.
Beyond simple sightseeing, visitors can connect with the history of early Edo-period civil engineering and the logistics that supported large-scale castle construction. Standing before the giant rock allows you to truly feel the scale of the work performed by the stonemasons and the advanced technology used to extract stone from nature. Exploring the site feels like a treasure hunt as you search for historical evidence through the various markings and symbols carved into the stones.
Shodoshima is home to many other historical ruins and scenic natural spots. You can easily create a travel itinerary that combines the natural beauty of the Tengu-iwa area with other historical routes across the island. The coexistence of Shodoshima's lush nature and the remnants of massive ancient engineering projects creates a unique landscape found only in this region.