Complete Guide to Tezutsuyama Castle (Tsuruga City, Fukui Prefecture) | A Crucial Base of the Asakura Clan that Supported Kanegasaki Castle
Overview of Tezutsuyama Castle
Tezutsuyama Castle (Tezutsuyama-jo) is a Sengoku period mountain castle built on Mount Tezutsuyama, 171.3 meters above sea level, in Tsuruga City, Fukui Prefecture. Also known as Tezutsu Castle, Tenzutsu Castle, and Tezutsuyama Castle, it functioned as a branch castle (sub-castle) of Kanegasaki Castle.
Mount Tezutsuyama is connected to Kanegasaki Castle by a ridge, and it is believed that the two castles operated as a single, integrated defensive system. The castle’s location is highly strategic; from the summit, one can see Tsuruga Bay, Tsuruga City, the old Hokuriku Road, and the entirety of Kanegasaki Castle. Due to this excellent view, it is presumed that Tezutsuyama Castle played a particularly important role as a lookout post and surveillance base.
Currently, it is part of Kanegasaki Park, with an observation deck, making it a popular scenic spot offering panoramic views of Tsuruga city and Tsuruga Bay, attracting many tourists and hiking enthusiasts.
History of Tentoyama Castle
Construction and Rule by the Asakura Clan
Tentoyama Castle was built by the Asakura clan, who ruled Echizen Province, as a subsidiary castle of Kanegasaki Castle. While Kanegasaki Castle was the main castle protecting the strategic point of Tsuruga, Tentoyama Castle functioned as an important defensive base fortifying its southern side.
As a Sengoku-period daimyo ruling Echizen Province, the Asakura clan considered Tsuruga, facing Wakasa Bay, an important port city, and strengthened Tsuruga’s defenses with a two-castle system of Kanegasaki Castle and Tentoyama Castle. While there are no clear records regarding the exact construction date of Tentoyama Castle, it has been suggested that it may have been added or renovated in later periods to complement the strengthening of Kanegasaki Castle’s defenses.
The Battle of Kanegasaki in 1570
Tentoyama Castle first appears on the historical stage during the Battle of Kanegasaki, which took place in April 1570. This battle was part of Oda Nobunaga’s invasion of Echizen Province.
Oda Nobunaga led a large army of approximately 100,000 men into Echizen Province and attacked Kanegasaki Castle and Tentoyama Castle. At this time, Terada Uneme-no-jo was the commander of Tentoyama Castle, while Asakura Kagetsune was defending Kanegasaki Castle.
On April 25th, Tentoyama Castle fell to a fierce attack by the Oda army. This battle was a fierce battle in which thousands of soldiers died on both sides. With the fall of Tentoyama Castle, Asakura Kagetsune was forced to withdraw his defenses to Kanegasaki Castle.
This battle involved not only Oda Nobunaga, but also Tokugawa Ieyasu and Toyotomi Hideyoshi (then known as Kinoshita Hideyoshi), who would later become unifiers of Japan, making it one of the most important battles in the history of the Sengoku period. In particular, the Oda army faced a pincer attack due to the betrayal of Asai Nagamasa, forcing Nobunaga to undertake the difficult retreat known as the “Retreat from Kanegasaki.” Kinoshita Hideyoshi famously distinguished himself by serving as the rearguard during this retreat.
Post-War Tentoyama Castle
After the Battle of Kanegasaki, detailed historical records of Tentoyama Castle become scarce. The Asakura clan was destroyed by Oda Nobunaga in 1573, and Echizen Province came under the control of the Oda family. Subsequently, as the era shifted to the Toyotomi regime and the Edo period, Tentoyama Castle is believed to have ceased its role as a military base and was abandoned.
Structure and Layout of Tentoyama Castle
Castle Layout
Tentoyama Castle is a large mountain castle spanning Tentoyama-cho, Izumi-cho, and Maizaki-cho in Tsuruga City. It is connected to Kanegasaki Castle by a ridge, and it is highly likely that the two castles were designed as a single defensive system.
The main enclosure (honmaru) is located at the summit of Mount Tentoyama, offering exceptional views. The view encompasses Tsuruga Bay, Tsuruga City, the old Hokuriku Road, and the entirety of Kanegasaki Castle, indicating a design that emphasized surveillance and lookout functions. In fact, because it is at a higher elevation than Kanegasaki Castle, it is sometimes described as “almost the main castle.”
Current Status of Remains
Currently, the remains of Tentoyama Castle are not clearly preserved. Due to years of weathering and later development, castle remains such as moats, earthworks, and baileys have become unclear. However, it is possible to infer the former castle area from the topography of the mountaintop and the shape of the ridge. Near the summit, there is an information board explaining the history of Tentoyama Castle and its relationship with Kanegasaki Castle. While the remains themselves are difficult to discern, you can feel the atmosphere of the Sengoku period and reflect on history.
Relationship with Kanegasaki Castle
Tentoyama Castle and Kanegasaki Castle are connected by a ridge, and the distance between the two castles is about 20 minutes on foot. Currently, it is a well-maintained hiking trail; by following the mountain path along the ridge from the first gate of Kanegasaki Castle, you can reach the observation deck on Tentoyama.
Due to this geographical proximity, it is thought that Tentoyama Castle functioned as a forward base or observation post for Kanegasaki Castle. It is highly probable that a coordinated system was in place, where enemy movements were detected at Tentoyama Castle and transmitted to Kanegasaki Castle.
Highlights of Tentoyama Castle
Spectacular View from the Summit Observation Deck
The greatest highlight of Tentoyama Castle is the view from the observation deck located at the summit. Despite being a relatively low mountain at an elevation of 171.3 meters, the unobstructed views allow for a 360-degree panoramic vista.
To the north lies Tsuruga Bay, and on clear days, you can see the mountains on the opposite shore. To the east, you can enjoy a panoramic view of Tsuruga city, offering a glimpse of its modern cityscape. To the west, you can see Kanegasaki Castle and Kanegasaki Shrine, giving you a real sense of their relative positions. To the south, the mountains of Tsuruga stretch out, allowing you to imagine the route of the old Hokuriku Road.
This excellent view makes it clear that this mountain played an extremely important role as a lookout post during the Sengoku period (Warring States period).
Hiking Route to Kanegasaki Castle
The ridge trail from Tentoyama Castle to Kanegasaki Castle is currently maintained as a hiking course. Walking this route allows you to experience the relative positions of the two castles and their defensive lines.
The path takes you through a lush forest, allowing you to enjoy the scenery of each season. In spring, the cherry blossoms; in early summer, the fresh greenery; and in autumn, the vibrant autumn leaves create a beautiful landscape, making this a course where you can enjoy both historical walks and nature observation.
Facilities at Kanegasaki Park
Tentoyama Mountain is part of Kanegasaki Park, and there are various facilities in the surrounding area. Historical and cultural sights such as Kanegasaki Shrine, Kanazaki Shrine, and the Hanakae no Komichi (Flower Exchange Path) are scattered throughout the area.
Especially in spring, it is known as a famous cherry blossom viewing spot, attracting many visitors. Combined with a tour of the castle ruins, this area offers a comprehensive way to enjoy the history and culture of Tsuruga.
Access and Climbing Route
Access by Public Transportation
From JR Tsuruga Station
- Take the “Gurutto Tsuruga Loop Bus” (community bus) on the sightseeing route and get off at the “Kanagasaki-gu” bus stop. The trailhead is approximately a 5-minute walk from there.
- By taxi, it’s approximately 10 minutes from Tsuruga Station.
- On foot, it’s approximately 30-40 minutes from Tsuruga Station.
With the opening of the Hokuriku Shinkansen, access to Tsuruga Station has greatly improved. Day trips from the Tokyo area are now possible.
Access by Car
Using the Expressway
- Approximately 10 minutes from the Hokuriku Expressway “Tsuruga IC”
- Free parking is available near Kanegasaki-gu Shrine (approximately 50 spaces).
The trailhead is just a few minutes’ walk from the parking lot, making access easy. However, it can get crowded during cherry blossom season and on weekends, so early arrival is recommended.
Ascent Route
Route via Kanegasaki Shrine (Recommended)
- Park your car in the Kanegasaki Shrine parking lot.
- Visit Kanegasaki Shrine.
- From the first gate of Kanegasaki Castle, take the hiking trail.
- Walk along the ridge for about 20 minutes to the summit of Tentoyama.
This route consists of well-maintained stairs and walking paths, making it a relatively easy course. However, since there are many stairs, we recommend wearing appropriate athletic shoes.
Direct Ascent Route from Tentoyama Trailhead
In addition to Kanegasaki Shrine, there is also a direct trailhead to Tentoyama. This route mainly consists of uphill sections and is slightly steeper than the route via Kanegasaki Shrine, but it takes less time.
Estimated Time Required
- From trailhead to summit: Approximately 15-25 minutes
- Sightseeing and rest at the summit: Approximately 20-30 minutes
- If including the traverse to Kanegasaki Castle: Add 40-60 minutes
- Total time required: Approximately 1.5-3 hours
The time required will vary depending on your physical fitness and the level of detail you wish to explore, but half a day is sufficient to fully enjoy the experience.
Points to Note and Advice for Visitors
Clothing and Equipment
- Shoes: Athletic shoes or trekking shoes are recommended. Avoid sandals as there are many stairs.
- Clothing: Comfortable clothing. Take appropriate precautions against cold or heat depending on the season.
- Items to Bring: Drinks, towel, insect repellent (summer), rain gear
Although the elevation is low, it is safer to wear light hiking gear as you will be walking on mountain trails.
Best Season for Visiting
- Spring (late March to April): The most popular season, with beautiful cherry blossoms. However, it can get crowded.
- Early Summer (May-June): Beautiful fresh greenery and mild weather. Relatively uncrowded.
- Autumn (October-November): Stunning autumn foliage and comfortable temperatures.
- Winter (December-February): Snow can accumulate, so caution is needed underfoot. Fewer visitors.
Visiting Hours
While there are no specific opening or closing times for the Tentoyama Castle ruins, visiting during daylight hours is recommended. Especially in winter, sunset is early, so visiting early in the afternoon is safer.
Nearby Tourist Attractions
Kanegasaki Castle Ruins
Kanegasaki Castle, connected to Tentoyama Castle by a ridge, is a must-see spot to visit in conjunction with Tentoyama Castle. It was the main battlefield of the Battle of Kanegasaki, and many remains still exist.
Kanegasaki Shrine
A shrine built on the site of Kanegasaki Castle, dedicated to Prince Tsunenaga and Prince Takanaga, who died in battles during the Nanboku-cho period. Also known as a god of matchmaking, it is famous for its “Hana-kae Matsuri” (Flower Exchange Festival).
Tsuruga Red Brick Warehouse
A tourist facility renovated from red brick warehouses built during the Meiji era. It features a diorama museum showcasing Tsuruga’s history as a port town, and a restaurant.
Kehi Shrine
The Ichinomiya (first-ranked shrine) of Echizen Province, located in the heart of Tsuruga City. Its large torii gate is one of Japan’s three largest wooden torii gates and is designated a National Important Cultural Property.
Port of Humanity Tsuruga Museum
A museum showcasing Tsuruga’s history of accepting Jewish refugees during World War II. A facility that prompts reflection on humanity and peace.
Tips for Enjoying Tentoyama Castle
Study the Historical Background Beforehand
Since the remains of Tentoyama Castle are not clearly defined, learning about the Battle of Kanegasaki, the Asakura clan, and Oda Nobunaga before your visit will enhance your enjoyment. Knowing the story of the “Retreat from Kanegasaki” will particularly increase your appreciation of the site.
Visit in Combination with Kanegasaki Castle
Tentoyama Castle alone offers limited sights, so visiting it in conjunction with Kanegasaki Castle and Kanegasaki Shrine will make for a more fulfilling historical exploration. Experiencing the relative locations of the two castles firsthand will help you understand the defensive system of the Sengoku period.
Enjoy the View from the Observation Deck
Even with few remaining structures, the view from the observation deck is magnificent. Imagine what the warlords of the Sengoku period saw from this spot while overlooking Tsuruga Bay and the city.
Best Photo Spots
- View of Tsuruga Bay from the mountaintop observation deck
- Ridge trail towards Kanegasaki Castle
- Spring cherry blossoms and Tsuruga cityscape
- Hiking trail surrounded by autumn foliage
Historical Significance of Tentoyama Castle
Tentoyama Castle, viewed in isolation, is merely a small subsidiary castle. However, its importance becomes clear when considered as part of a defense system integrated with Kanegasaki Castle.
During the Sengoku period, the Asakura clan established a two-castle system of Kanegasaki Castle and Tentoyama Castle to protect Tsuruga, which was an important port city. Tentoyama Castle, in particular, is thought to have played a role in surveillance and lookout functions due to its excellent visibility, allowing for early detection of enemy movements.
In the Battle of Kanegasaki in 1570, future rulers of Japan—Oda Nobunaga, Tokugawa Ieyasu, and Toyotomi Hideyoshi—participated, and a fierce battle unfolded. This battle was one of the few toughest for Oda Nobunaga and is remembered in Sengoku period history as the “Retreat from Kanegasaki.”
Although few remains exist today, Tentoyama Castle, along with Kanegasaki Castle, is an important historical site that tells the story of Tsuruga’s history and should be passed down to future generations.
Summary
Tentoyama Castle is a mountain castle located in Tsuruga City, Fukui Prefecture, at an altitude of 171.3 meters. It was built by the Asakura clan as a subsidiary castle of Kanegasaki Castle. In the Battle of Kanegasaki in 1570, it was attacked by a large army led by Oda Nobunaga and fell after a fierce battle.
Although the remains are not clearly visible today, the observation deck at the summit offers a panoramic view of Tsuruga Bay and the city, allowing one to appreciate its role as a lookout post during the Sengoku period. It is connected to Kanegasaki Castle by a ridge, and both castles can be visited via a hiking trail.
Access is good, about 10 minutes by bus or taxi from JR Tsuruga Station, or about 40 minutes on foot. The climb from the trailhead to the summit takes about 15-25 minutes, and it’s easily accessible with appropriate walking shoes.
While Tentoyama Castle alone has limited attractions, visiting it in conjunction with Kanegasaki Castle, Kanegasaki Shrine, and other tourist spots in Tsuruga city allows you to enjoy Tsuruga’s rich history and culture comprehensively. This spot is recommended for those interested in the history of the Sengoku period, those who enjoy visiting castle ruins, and those who want to enjoy a light hike.
