Niitakayama Castle Complete Guide | History and Highlights of the Continued Top 100 Japanese Castles Built by Kobayakawa Takakage
Niitakayama Castle is a Sengoku period mountain castle located in Hongō-chō, Mihara City, Hiroshima Prefecture. It was the base of Kobayakawa Takakage, a brilliant general known as the third son of Mōri Motonari. In 2017, it was selected as one of the Continued Top 100 Japanese Castles (number 173) and is also designated a national historic site. Built on a mountaintop at an altitude of 197.6 meters and a relative height of 186 meters, this castle supported the prosperity of the Kobayakawa clan for approximately 45 years as a base for expansion into the Seto Inland Sea.
History of Niitakayama Castle
Background of Construction and Kobayakawa Takakage
The history of Niitakayama Castle begins with a full-scale renovation carried out by Kobayakawa Takakage in 1552 (Tenbun 21). Takakage was born the third son of Mori Motonari and succeeded to the Kobayakawa clan as the 17th head of the family. Until then, the Numata Kobayakawa clan had used Takayama Castle on the east bank of the Numata River as their ancestral residence, but Takakage decided to build a new castle on a mountain on the west side of the opposite bank.
This decision was driven by a strategic intention to expand into the Seto Inland Sea. As the Mori clan established its hegemony in the Chugoku region, control of the Seto Inland Sea, a crucial maritime transportation hub, was extremely important. Takakage led a naval force to expand his power in the Seto Inland Sea, and Shin-Takayama Castle served as its base.
45 Years as the Kobayakawa Clan’s Base
From 1552 (Tenbun 21) to 1596 (Keicho 1), Shin-Takayama Castle flourished as the Kobayakawa clan’s base. For the past 45 years, Takakage has been based at Niitakayama Castle, participating in numerous battles and serving as a key retainer of the Mori clan.
Takakage was not merely a military commander, but also a skilled statesman. He governed a vast territory stretching from eastern Hiroshima Prefecture to the Seto Inland Sea coast, and dedicated himself to promoting commerce. A castle town developed around Niitakayama Castle, flourishing as a center for the collection and distribution of goods, utilizing the Numata River’s water transport.
Relocation to Mihara Castle and the End of Niitakayama Castle
In 1596 (Keicho 1), Kobayakawa Takakage began construction of Mihara Castle as his new base. Mihara Castle was a flatland castle facing the sea, and was expected to become a more efficient hub for maritime transportation. For the construction of Mihara Castle, the stone walls of Niitakayama Castle were dismantled and reused as building materials.
With this relocation, Niitakayama Castle ended its approximately 45-year service and was abandoned. However, its remains are well-preserved and are now valued as a precious historical site that conveys the appearance of a mountain castle from the Sengoku period.
Structure of Niitakayama Castle
Layout and Overall Arrangement
Niitakayama Castle is a large mountain castle measuring approximately 400 meters east-west and 500 meters north-south. The entire mountain was fortified, and it has a complex structure with multiple baileys arranged in a stepped pattern.
The main keep, the heart of the castle, is located at the mountaintop, and multiple baileys extend from there along the ridge. The layout, which skillfully utilizes the terrain, demonstrates the high level of castle-building technology of Kobayakawa Takakage. It is characterized by a structure that is easy to defend even with a small force, by taking advantage of the steep terrain.
Main Keep and Major Baileys
The main keep is located at the highest point of the castle, offering panoramic views of the surrounding area. Even today, parts of the stone walls remain at the site of the main keep, giving a glimpse of its former grandeur. From the main keep, one can see the flow of the Numata River, the ruins of Takayama Castle on the opposite bank, and even the Seto Inland Sea, giving a real sense of its strategic location as a military stronghold.
Several baileys were arranged around the main keep, each functioning as a defensive base. The baileys were separated by steep slopes and trenches, demonstrating ingenuity in making enemy intrusion difficult.
Stone Walls and Remains
While much of the stone walls of Shin-Takayama Castle were dismantled during the construction of Mihara Castle, some still remain. These stone walls were built using a technique called “nozurazumi” (rough stone masonry), making them valuable resources for understanding castle construction techniques of the Sengoku period.
Other remains include well remains, earthworks, and trenches. Of particular note is the well called “Tsurubei,” located near the main keep, which served as an important water source for the castle. Securing water was a matter of life and death for mountain castles, and the existence of this well indicates that Niitakayama Castle was designed to withstand a long siege.
Defensive Structures and Military Features
Niitakayama Castle’s defensive structures made maximum use of the natural terrain. The steep slopes themselves served as natural barriers, and trenches were dug along the ridges to hinder enemy advances.
The arrangement of the baileys was also strategic; even if the enemy breached one bailey, they would be attacked from the flank by the next. This type of layout is called “yokoyagakari” (flanking fire) and is a common defensive technique in mountain castles of the Sengoku period.
From the mountaintop, the surrounding movements could be monitored, allowing for early detection of approaching enemies. It also functioned as a signal fire station and is thought to have been used as a means of communication with other Mori clan strongholds.
Highlights of Niitakayama Castle
Ascent Route and Time Required
The ascent to Niitakayama Castle begins from the trailhead near the Hongō Lifelong Learning Center. The hiking trail is well-maintained, making it a relatively easy route for a mountain castle. From the trailhead to the main keep, it takes approximately 40 to 50 minutes at a normal pace.
While there are some steep sections, guide signs are placed throughout, ensuring even beginners won’t get lost. The trail passes through several former baileys, allowing hikers to experience the castle’s structure firsthand.
View from the Main Keep
Upon reaching the main keep, a breathtaking panoramic view awaits. You can see the meandering Numata River, the ruins of Takayama Castle on the opposite bank, and even the islands of the Seto Inland Sea in the distance. This view speaks volumes about why Kobayakawa Takakage chose this location as his base.
On clear days, you can enjoy a panoramic view of Mihara city and the beautiful archipelago of the Seto Inland Sea, reliving the scenery seen by the lords of the Sengoku period. You can also enjoy the changing seasons, with cherry blossoms in spring and autumn leaves in fall.
The Well and Water Supply
The well located near the main keep is one of the important highlights of Shintakayama Castle. This well, approximately 20 meters deep, provided an abundant water supply despite its mountaintop location. The well’s structure can still be seen today, showcasing the impressive civil engineering techniques of the Sengoku period.
Securing a water source was paramount for mountain castles, and the existence of this well underpinned Shintakayama Castle’s strength. Even in the event of a siege, a water supply would have allowed the castle to withstand attacks for extended periods.
Stone Walls and Enclosure Remains
The stone walls remaining throughout the castle are valuable remnants that were not completely dismantled during the relocation to Mihara Castle. The rough-hewn stone walls, constructed using a technique of stacking natural stones, have a simpler appearance compared to later techniques like cut-stone jointing, but this gives them a strong sense of the Sengoku period.
By actually walking around and examining the layout of each enclosure, you can experience the ingenuity of the castle’s design. Understanding the actual defensive capabilities, such as the elevation differences between baileys and the depth of the moats—details not apparent from blueprints alone—allows for a deeper understanding of the castle’s actual defensive capabilities.
Relationship with Takayama Castle
An essential aspect of discussing Shin-Takayama Castle is its relationship with Takayama Castle, located across the Numata River. Takayama Castle was the ancestral home of the Numata Kobayakawa clan and their base before Shin-Takayama Castle was built.
Even after Kobayakawa Takakage built Shin-Takayama Castle, Takayama Castle was not completely abandoned. A system was established where both castles worked together to control the Numata River basin. This arrangement of opposing castles is called “Mukaijiro” (opposing castles) and is one of the castle strategies of the Sengoku period, designed to create a stronger defensive system.
Currently, the Takayama Castle ruins are also designated as a national historic site. Visiting both Shin-Takayama Castle and Takayama Castle together allows for a deeper understanding of the Kobayakawa clan’s overall control over their territory.
Value as one of the Continued Top 100 Japanese Castles
On April 6, 2017, Niitakayama Castle was selected as the 173rd castle in the Continued Top 100 Japanese Castles. This selection was based on its historical value as a castle, the state of preservation of its remains, and its connection to the famous warlord Kobayakawa Takakage.
The Continued Top 100 Japanese Castles is the second selection following the Top 100 Japanese Castles selected in 2006, aiming to showcase the diverse appeal of castles. Among them, Niitakayama Castle is positioned as a typical example of a Sengoku period mountain castle and an important historical site for understanding the history of the Seto Inland Sea region.
For castle enthusiasts, the Continued Top 100 Japanese Castles stamp rally is a popular event, and Niitakayama Castle attracts many visitors. You can get a stamp for the Continued Top 100 Japanese Castles at the Hongo Lifelong Learning Center.
The Figure of Kobayakawa Takakage
Understanding the figure of Kobayakawa Takakage is essential when discussing the history of Niitakayama Castle. Takakage was born in 1533 as the third son of Mori Motonari. His older brothers were Mori Takamoto and Kikkawa Motoharu, and he played a key role in the “Two Rivers of Mori” system.
Takakage’s greatest characteristic was his comprehensive ability, excelling not only in military prowess but also in strategic intelligence. He distinguished himself in battles in the Seto Inland Sea by leading the navy, while also demonstrating skill in domestic affairs, successfully managing his domain. As the youngest of three brothers who received the “Three Arrows” lesson from Mori Motonari, he worked with his brothers to support the prosperity of the Mori clan.
During Toyotomi Hideyoshi’s invasion of the Chugoku region, he played a crucial role as a mediator between the Mori clan and Hideyoshi, and after the Honnoji Incident, he supported the Toyotomi regime as one of the Five Elders. He is known as a renowned general who lived through the Sengoku and Azuchi-Momoyama periods until his death at Mihara Castle in 1597.
Access and Visiting Information for Shintakayama Castle
Transportation Access
Access by Train
- Get off at JR Sanyo Main Line “Hongo Station,” then walk approximately 20 minutes to the trailhead.
- If using the Shinkansen, transfer to a local line at “Mihara Station.”
Access by Car
- Approximately 10 minutes from Sanyo Expressway “Hongo IC.”
- Parking available at Hongo Lifelong Learning Center (free).
Precautions When Visiting the Castle
Shintakayama Castle is a full-fledged mountain castle, so please note the following points when visiting:
- Clothing: Comfortable clothing and hiking boots or trekking shoes are recommended.
- Items to Bring: Drinking water, towel, insect repellent (summer).
- Estimated Time: Expect approximately 1.5 to 2 hours for a round trip from the trailhead to the main keep.
- Season: Spring and autumn are best. Take precautions against the heat in summer, and be mindful of sunset times in winter.
- Weather: Be careful as the trail can be slippery in rainy weather. Watch your step even after the rain.
Stamp and Guidance Facility
The stamp for the Continued Top 100 Japanese Castles is located at the Hongō Lifelong Learning Center (Hongō Town Cultural Hall). Opening hours are usually from 9:00 AM to 10:00 PM, but there are also closed days, so it is recommended to check in advance.
The center also displays materials related to Shintakayama Castle, and visiting before climbing the castle will deepen your understanding of it. Pamphlets are also available, so first-time visitors should definitely stop by.
Nearby Tourist Spots
When visiting Shintakayama Castle, visiting nearby historical sites and tourist spots will make your trip more fulfilling.
Takayama Castle Ruins
The former residence of the Kobayakawa clan, located on the opposite bank of the Numata River. Visiting it together with Shintakayama Castle will help you understand the Kobayakawa clan’s castle strategy. This is also designated as a national historical site.
Mihara Castle Ruins
The last residence of Kobayakawa Takakage, to whom he moved from Shintakayama Castle. Currently, remnants such as stone walls remain around JR Mihara Station, making it known as a “castle close to the station.” The castle tower base also exists, making it a historical site easily accessible from the city center.
Scenery of the Numata River
The Numata River, flowing between Shintakayama Castle and Takayama Castle, flourished as a vital water transport route since ancient times. From the riverside walking path, both castles can be viewed, allowing visitors to experience the topography of the Sengoku period.
Preservation and Utilization of Shintakayama Castle
The Shintakayama Castle ruins are protected as a national historical site, and the Mihara City Board of Education is leading efforts to preserve and utilize them. Regular mowing and maintenance of hiking trails are carried out to maintain a safe environment for visitors.
In recent years, further development has been underway following its selection as one of the Continued Top 100 Japanese Castles. Improvements to information boards and multilingual brochures are also being made to enhance its use as a tourist resource.
Local volunteer guides are also available, and it is possible to climb the castle while receiving more detailed explanations by making a reservation in advance. Expert commentary significantly deepens your understanding of the ruins and their historical context.
Summary
Shintakayama Castle is a historical site that played an important role as a mountain castle built by Kobayakawa Takakage, a leading strategist of the Sengoku period, and as a base for expansion into the Seto Inland Sea. Its selection as one of the Continued Top 100 Japanese Castles has brought its value nationwide recognition.
The castle, built on a mountaintop approximately 200 meters above sea level, requires physical exertion to reach, but the view from the main keep and the remaining ruins are well worth the effort. Shintakayama Castle, which preserves the appearance of a Sengoku period mountain castle in excellent condition, is a recommended spot not only for history buffs but also for those who enjoy mountain climbing and hiking.
By visiting Takayama Castle on the opposite bank of the Numata River and Mihara Castle, where Takakage last moved, you can enjoy a historical journey tracing the footsteps of Kobayakawa Takakage. When you visit Hiroshima Prefecture, be sure to stop by Shintakayama Castle and experience the atmosphere of the Sengoku period.
