Guide
Kaminokuni Katsuyama-kan is a medieval Japanese mountain castle (yamajiro) located in Kaminokuni Town, Hiyama District, Hokkaido. It was designated as a National Historic Site in 1977 and was selected as one of the 'Continued 100 Famous Castles of Japan' in 2017. The site features a large-scale structure utilizing the slopes of Mt. Iou, spanning an area of approximately 20.9 hectares. Historically, this location served as a vital stronghold, once acting as the base for the Kaki clan or as a significant secondary castle.
While the exact date of construction is not definitively recorded, the founding of the 'Kanshinyu Hachiman-gu' shrine at the northern end of the site is dated to 1473 (Bunmei 5), leading historians to estimate the castle was built in the late 15th century. Originally the seat of the Kaki clan, it later became known as 'Waki no Tate' (the Waki residence/castle) after the clan moved their base to Tokuyama-kan in Matsumae during the early 16th century. Post-war archaeological-surveys have unearthed an extraordinary collection of approximately 70,000 artifacts, including ceramics, metalware, lacquerware, and bone-and-antler tools from the late 15th to late 16th centuries. Notably, 921 of these items have been designated as National Important Cultural Properties.
The primary draw of this site is the massive volume of unearthed artifacts that provide a window into medieval life and defense strategies. The ceramics and metalware serve as precious records of the cultural standards of that era. Additionally, the topographical layout utilizing the mid-slope of Mt. Iou and the nearby Iou-san Tumuli (ancient Japanese burial mounds) form a significant part of the historical landscape. Exploring these ruins allows visitors to see how ancient engineers skillfully utilized natural terrain for fortification.
The site can be explored throughout the year, offering a unique experience of walking through medieval castle ruins amidst the natural beauty of Mt. Iou. The scenery changes beautifully with the seasons, providing different perspectives on the historical landscape. However, as this is a mountain castle site, please be mindful of the terrain and footing, which can change depending on the weather and season.
Visitors can engage in an intellectual exploration of Japanese castle culture and medieval history. By observing the vast array of excavated artifacts and the strategic layout of the terrain, you can visualize the daily lives and defensive mechanisms of the people who once lived here. Walking through this historical landscape offers a profound sense of time travel.
Kaminokuni Town is dotted with other historical remains and sites that tell the story of the local region. You can easily incorporate a visit to Katsuyama-kan into a larger cultural itinerary exploring the rich history and natural beauty of the area.