Complete Guide to Otaka Castle (Nagoya City, Aichi Prefecture) | A National Historic Site and the Site of a Prelude to the Battle of Okehazama
Located in Otaka-cho, Midori-ku, Nagoya City, Aichi Prefecture, Otaka Castle is a castle site that played an important role in the Sengoku period (Warring States period). It is particularly known as the site where the young Matsudaira Motoyasu (later Tokugawa Ieyasu) made a desperate attempt to deliver provisions during the Battle of Okehazama in 1560. Currently, it is maintained as Otaka Castle Ruins Park and, along with the Marune Fort Ruins and Washizu Fort Ruins, is designated as a national historic site.
Overview and Basic Information of Otaka Castle
Otaka Castle is a flatland castle built in Otaka Village, Chita District, Owari Province (present-day Shiroyama, Otaka-cho, Midori-ku, Nagoya City). Situated on a plateau approximately 20 meters high, it once had a strong structure surrounded on all four sides by double moats.
Location: Shiroyama, Odaka-cho, Midori-ku, Nagoya City, Aichi Prefecture
Castle Structure: Hilltop castle
Construction Period: Eisho era (1504-1521) or possibly the Nanboku-cho period
Main Lords: Hanai Bichu-no-kami, Mizuno clan, Udono clan (under the Imagawa clan), etc.
Designated Cultural Property: National Historic Site (designated in 1938)
Current Status: Developed as Odaka Castle Ruins Park
History of Odaka Castle
Construction and Early History
There are various theories regarding the construction period of Odaka Castle, but the most widely accepted theory is that it was built during the Eisho era (1504-1521) by Hanai Bichu-no-kami, a vassal of the Toki clan, the shugo (military governor) of Owari Province. On the other hand, some researchers suggest it may date back to the Nanboku-cho period.
The Mizuno Clan Era
From the Tenbun era to the Koji era (1532-1558), the Mizuno clan, based at Ogawa Castle, expanded their power and became the lords of Otaka Castle. The Mizuno clan was a powerful Sengoku daimyo with influence throughout the Chita Peninsula, and Otaka Castle functioned as an important base in southern Owari Province.
During the Mizuno era, Otaka Castle was strategically important as a buffer zone between Oda Nobuhide’s (Oda Nobunaga’s father) movement to unify Owari and the expansion of the Imagawa clan.
Under Imagawa Control
Around 1556 (Koji 2), Otaka Castle is believed to have come under the control of Imagawa Yoshimoto. The Imagawa clan positioned Otaka Castle as an important front-line base in their expansion into Owari. During this period, the castle lord is thought to have been the Udono clan, vassals of the Imagawa clan.
The Battle of Okehazama and the Supplying of Food
In May 1560 (Eiroku 3), Otaka Castle became the site of a preliminary battle for the Battle of Okehazama, one of the most famous battles in Japanese history.
At the time, Oda Nobunaga adopted a strategy of besieging Otaka Castle to counter Imagawa Yoshimoto’s invasion of Owari Province. In 1559 (Eiroku 2), he built Marune Fort and Washizu Fort around Otaka Castle, attempting to isolate it. This led to a critical situation where Otaka Castle faced a shortage of food supplies.
From the night of May 18th to the early morning of May 19th, Matsudaira Motoyasu (later Tokugawa Ieyasu, then 19 years old), acting on orders from Imagawa Yoshimoto, broke through the Oda’s encirclement and carried out a supplying of food to Otaka Castle. This operation was successful, and Motoyasu succeeded in delivering food supplies to Otaka Castle.
Subsequently, in the early morning of May 19th, Motoyasu attacked and captured Marune Fort. Almost simultaneously, Asahina Yasutomo of the Imagawa forces attacked and captured Washizu Fort. However, later that day, Imagawa Yoshimoto was killed in a surprise attack by Oda Nobunaga at Okehazama, and the Imagawa army collapsed completely.
After the Battle of Okehazama
After the Battle of Okehazama, Otaka Castle is believed to have left the Imagawa clan’s sphere of influence and eventually came under the control of the Oda clan. While the detailed history of the castle after that is unclear, it is presumed that its military role ended with the end of the Sengoku period.
Current Status of Otaka Castle Ruins
Development as Otaka Castle Ruins Park
Currently, the Otaka Castle ruins have been developed by Nagoya City as Otaka Castle Ruins Park, serving as a place of recreation for citizens. Despite its location in the heart of the city, the site was designated a national historic site early on, resulting in excellent preservation of the remains and conveying the atmosphere of a Sengoku period castle.
The park features information boards and explanatory signs, allowing visitors to learn about the castle’s history and structure. It’s also known as a famous cherry blossom viewing spot, attracting many visitors in spring.
Preserved Remains
The following remains can be observed at the Ootaka Castle ruins:
Main Enclosure Site: The remains of the main enclosure (honmaru), the central part of the castle, are well-preserved. Currently a flat area, it allows visitors to appreciate the scale of the former castle.
Second Enclosure Site: The remains of the second enclosure (ni-no-maru), adjacent to the main enclosure, can also be seen.
Moat Remains: While it’s believed that a double moat once surrounded the castle on all four sides, only faint traces of the moat remain today. Traces of a dry moat are particularly noticeable around the main enclosure.
Earthen Bridge: The remains of an earthen bridge used to cross the moat remain, providing insight into the castle’s entrances and exits at the time. Earthen bridges were an important element of castle architecture and are valuable remains for understanding Ootaka Castle’s defensive system.
Earthwork Remains: Partial traces of earthworks built to defend the castle can also be seen.
These remains clearly demonstrate the characteristics of castle architecture from the Sengoku period (Warring States period), and their value as a historical site is highly regarded.
Value as a National Historic Site
The Ootaka Castle ruins were designated a national historic site in 1938, along with the Marune Fort ruins and the Washizu Fort ruins. This was due to the recognition of its historical value as a site related to the Battle of Okehazama, a crucial battle in Japanese history.
The fact that the three historic sites are designated as a single entity indicates their close connection in the preliminary battles leading up to the Battle of Okehazama. The structure of Marune Fort and Washizu Fort, built by Oda Nobunaga to besiege Ootaka Castle, and Ootaka Castle, where Matsudaira Motoyasu supplied provisions in response, illustrates the strategic situation at the time.
Sub-castles, Nearby Facilities, and Related Spots
Marune Fort Ruins
Located approximately 1 kilometer southeast of Otaka Castle, Marune Fort was built by Oda Nobunaga in 1559 to besiege Otaka Castle. It was attacked and captured by Matsudaira Motoyasu in the early morning of the Battle of Okehazama. Currently, the Marune Fort Ruins are designated as a national historic site, and remnants such as earthworks remain.
Washizu Fort Ruins
Located approximately 1.5 kilometers southwest of Otaka Castle, Washizu Fort, like Marune Fort, was built by Oda Nobunaga to besiege Otaka Castle. It was attacked and captured by Asahina Yasutomo of the Imagawa clan on the day of the Battle of Okehazama. This site is also designated as a national historic site.
Battlefield of Okehazama
The main battlefield of the Battle of Okehazama is located approximately 5 kilometers west of Otaka Castle. The area spanning Midori Ward in Nagoya City and Toyoake City contains several historical battlefield sites. Visiting these sites along with Otaka Castle will allow for a deeper understanding of the overall picture of the Battle of Okehazama.
Hikawa Aneko Shrine
Located near Otaka Castle, Hikawa Aneko Shrine is a shrine with a legend that Matsudaira Motoyasu prayed here for the success of his military supply runs. It is also known as a place associated with Tokugawa Ieyasu.
Access and Transportation to Otaka Castle
Access by Public Transportation
JR Tokaido Main Line: Get off at Otaka Station, approximately 15 minutes on foot
Meitetsu Nagoya Main Line: Get off at Sakyoyama Station, approximately 20 minutes on foot
Access from JR Otaka Station is the most convenient. The path from the station to the castle ruins is flat, and you can enjoy the old townscape of Otaka along the way.
Access by Car
Nagoya Expressway: Approximately 10 minutes from the Kasadera exit
Isewangan Expressway: Approximately 15 minutes from the Nagoya Minami Interchange
There is no dedicated parking lot around the castle ruins, but you can use nearby coin-operated parking lots. However, since the number of spaces is limited, we recommend using public transportation.
Points to Note During Your Visit
Ootaka Castle Ruins Park is always open and you can visit freely. The visit takes approximately 30 minutes to 1 hour.
To gain a deeper understanding of the castle ruins, we recommend acquiring some basic knowledge about the Battle of Okehazama and castle architecture during the Sengoku period beforehand. Visiting Ootaka Castle Ruins along with Marune Fort Ruins and Washizu Fort Ruins will allow you to grasp the overall picture of the preliminary battles leading up to the Battle of Okehazama.
Ootaka Castle and Tokugawa Ieyasu
Ootaka Castle is a place of great significance in the life of Tokugawa Ieyasu (Matsudaira Motoyasu). At the young age of 19, his daring and successful delivery of provisions is recounted as an episode demonstrating his bravery and judgment, which would later lead to him becoming the unifier of Japan.
At the time, Motoyasu had only recently been released from captivity by the Imagawa clan, and this delivery of provisions to Otaka Castle was his first major military operation under Imagawa Yoshimoto. His successful completion of this dangerous mission, breaking through the Oda forces’ encirclement, earned him Imagawa Yoshimoto’s trust.
However, ironically, just a few hours after this successful delivery, Imagawa Yoshimoto was killed at Okehazama. This event dramatically changed Motoyasu’s life, eventually leading him to break away from the Imagawa clan and embark on the path to unifying Japan as Tokugawa Ieyasu.
Therefore, Otaka Castle is a historically significant site, marking a crucial turning point in Tokugawa Ieyasu’s life.
Highlights and Ways to Enjoy Ootaka Castle
Attractions for History Fans
Ootaka Castle is a must-see for history buffs, as it is a historical site associated with the Battle of Okehazama, one of the most important battles in Japanese history. Especially for those interested in the Sengoku period or Tokugawa Ieyasu, visiting the site of his youthful exploits will allow you to feel closer to history.
By standing on the castle ruins and observing the surrounding terrain, you can understand why the castle was built in this location and how it was defended. Furthermore, by examining its positional relationship with Marune Fort and Washizu Fort, you can concretely visualize Oda Nobunaga’s siege strategy and the Imagawa’s response.
A Place of Relaxation for Citizens
Ootaka Castle Ruins Park is not only a historical site but also a popular place of relaxation for local residents. It is a well-maintained park with lush greenery, offering various ways to enjoy it, such as walking, jogging, and picnicking.
In spring, the cherry blossoms bloom, making it a famous spot for cherry blossom viewing. Enjoying cherry blossoms in a historical atmosphere is a special experience.
Educational Value
The Ootaka Castle ruins are also used as a site for history learning in schools. Local elementary and junior high schools sometimes conduct field trips to Ootaka Castle to learn about local history.
Visiting actual historical sites allows for a more concrete understanding of history learned in textbooks, deepening children’s interest in history.
Historical Environment Around Ootaka Castle
The Ootaka area has flourished as a transportation hub since ancient times. Located between Narumi-juku, a post town on the Tokaido road, and the Chita Peninsula, it was a bustling center for the movement of goods and people.
These geographical conditions are one of the reasons why Ootaka Castle became an important strategic base during the Sengoku period (Warring States period). Near the border of Owari and Mikawa provinces, and as the gateway to the Chita Peninsula, Ootaka was an indispensable location for controlling this region.
Even today, the town of Ootaka retains old townscapes and temples and shrines, allowing visitors to experience a historical atmosphere. When visiting Ootaka Castle, we recommend exploring the surrounding historical environment as well.
Summary
Ootaka Castle, located in Midori Ward, Nagoya City, Aichi Prefecture, is a historically valuable site that served as the stage for a preliminary battle leading up to the Battle of Okehazama, a crucial battle in Japanese history. It holds great significance as the place where a young Tokugawa Ieyasu successfully carried out a desperate supply run, and as a site that preserves the remains of a castle from the Sengoku period.
Protected as a nationally designated historical site, the Ootaka Castle ruins still allow visitors to see remnants such as moats, earthen bridges, and earthworks, giving a glimpse into the castle’s appearance at the time. Along with the Marune Fort and Washizu Fort ruins, it forms a group of historical sites essential for understanding the overall picture of the Battle of Okehazama.
Ootaka Castle Ruins Park, a popular recreational spot for both history buffs and local residents, is a valuable historical spot easily accessible within Nagoya City. Why not reflect on the exploits of young Tokugawa Ieyasu while feeling the romance of the Sengoku period?
