In 1440, Japan was in the Muromachi Period, the early phase of the violent Sengoku, or Warring States period, marked by frequent localized wars. To control territories, many castles were built. One local warrior capitalized on the strategically situated 85-meter-high Inuyama Hill, surrounded by the natural moat of the Kiso River, offering clear views of the Nobi Plain and the ancient lands of Owari (Western Aichi) and Mino (Gifu).

Almost a century later, in 1537, Oda Nobuyasu, grandfather of the great Oda Nobunaga, took the hill and fortress, also known as Hakutei Castle. Recognizing its strategic importance, the Oda clan constructed a larger, sturdier, and more elegant castle. This became the first castle owned outright by Oda Nobunaga, although he left his uncle as a caretaker while he engaged in further battles.

Inuyama Castle, classified as a Hirayama-jiro, is the oldest of Japan's 12 remaining original castles. Located in Aichi Prefecture, it may seem small compared to others like Nagoya or Osaka castles. Its stone walls stand just five meters high, with the tower itself a mere 19 meters on top of that. The total floor space of the defensive tower structure is around 699 square meters, comparable to Hikone Castle, which is quite large for its time.


Today, only the keep, the main watchtower, remains. The lord's living quarters once occupied the wide flat area along the lower slopes of the mountain, which was fortified with turrets, barracks, walled corridors, and related buildings. Inuyama had nine yagura watchtowers around its perimeter and two main gates, with six smaller gates protecting the Honmaru.

Unlike most castles that name their precincts Honmaru, Ni-no-Maru, San-no-Maru, etc., Inuyama Castle's five baileys were named after trees, with the Honmaru at the top, and the lower slopes consisting of the Sumi, Momi, Kiri, and Matsu kuruwa.

The castle's architectural beauty is evident both inside and out. The tower is a four-story Borogata-type keep, with entry via the smallest anakura (basement) of all the castles in Japan. Steep stairs, built to save space and hinder armored invaders, lead to the spacious first floor.


The keep appears to be square, yet the northeastern corner features the widest open angle of any keep in Japan, providing better views and increased firing range along the eastern flank. The first floor is divided into several rooms, including the Jodan-no-Ma, the lord's official audience chamber, which is rare to find in a tower keep. This room features hidden doors in the wall, behind which the lord's bodyguards or a private retreat could be found.

Wide corridors called Musha-Bashiri (warrior running corridors) around these central rooms allowed defenders ample space to move during an attack. The first-floor Musha-Bashiri has six places where sliding doors once stood, reflecting an old style seen in Oda Nobunaga's Azuchi and Toyotomi Hideyoshi's Osaka Castles. However, these doors would hinder warriors' movements, preventing them from running around the central area.

Climbing to the second floor, you find the armory where weapons and armor were stored. The third story features wide outer corridors for warriors, especially archers, to move freely. Above that, small balconies under triangular eaves (hafu) provide fine views of the river and mountains and serve as firing positions. The fourth floor is a wide chamber with a low balcony offering spectacular views of the surrounding area.


The mid-section karahafu decorative curved roofing element and extended yagura watchtower were added during the Naruse years.

Inuyama Castle saw significant action, notably during the Battle of Komaki-Nagakute in 1584 when Toyotomi Hideyoshi used it as a base against Tokugawa Ieyasu. In 1600, it was threatened during the Battle of Sekigahara. The night before the battle, daimyo Takenaka Shigekado defected to the Eastern forces, and Ishikawa Sadakiyo, the lord of Inuyama, made a secret deal with the Eastern forces, securing the castle's future.

After a succession of lords, Naruse Masanori took control in 1617, and the castle remained in the Naruse family for generations. In 1871, after the feudal system ended, many of the castle's outer walls and buildings were destroyed. The main keep survived but was damaged in the 1890 Great Nobi Earthquake. The former Lord Naruse undertook repairs, and in 1935, Inuyama Castle was designated a National Treasure. It remained in the Naruse family's care until 2004 when it was handed over to Inuyama City and a new overseeing foundation.

Inuyama Castle is a fine example of 16th-century castle architecture and a treasured symbol of Inuyama City.


See also 

  • Ueda Castle


    Ueda Castle in Nagano Prefecture once stood prominently on a cliff overlooking the Saigawa River. Also known as Amagafuchi-Jo, Isesaki-Jo, Matsuo-Jo, and Sanada-Jo, it was built around 1583 by its first master, Sanada Masayuki. This sturdy yet small fortress cleverly utilized the surrounding natural defenses, including the river, steep rocky cliffs, the layout of the town below, and the strategically designed waterways to hinder attackers. Ueda Castle was fortified with seven defensive yagura (watchtowers) atop robust stone walls and had two large gates with watchtowers above them.

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  • Tsuyama Castle


    Tsuyama Castle, located in Tsuyama City, Okayama Prefecture, is celebrated as one of Japan's top three major hilltop (Hirayama) castles, alongside Himeji and Matsuyama Castles. Originally, Tsuyama Castle comprised 77 structures, including the main keep, various yagura (watchtowers), gates, palaces, and living quarters. For comparison, Hiroshima Castle had 76 structures, and Himeji had 61. The first castle on this site was built in 1441 but was soon abandoned. The large-scale construction that we recognize today began in 1603 under the orders of Mori Tadamasa. The castle served as the administrative base for the Tsuyama Han daimyo, the Mori clan from 1603 to 1697, and the Matsudaira clan from 1698 to 1871.

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  • Tsu Castle


    Tsu Castle, located in Tsu City, Mie Prefecture, was originally built by Hosono Fujiatsu in 1558 and was known as Anotsu Castle, named after the old region. The site was strategically chosen at the confluence of the Ano and Iwata Rivers, which naturally formed a moat around the castle, while the nearby port served as a vital trade route.

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  • Sasayama Castle


    Tamba Sasayama Castle, also known as Sasayama or Kirigajo (Mist Castle), is a flatland castle (hira-jiro) situated on a gentle rise in the Tamba region of Hyogo Prefecture. It was constructed in 1608 as part of Tokugawa Ieyasu's strategy to prepare for an attack on Osaka, aiming to bring an end to the Toyotomi clan. Ieyasu ordered the castle's construction using the Tenka Bushin system, engaging 20 former enemy daimyo and their forces to complete the complex within six months. This system kept the former enemies close and preoccupied, financially straining them and limiting their capacity for further conflict. The stones used in Sasayama Castle feature engravings called kokumon, indicating who made each part of the walls and preventing theft by other lords' men.

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  • Sadowara Castle


    Sadowara Castle in Miyazaki Prefecture was a mountaintop yamajiro castle, initially built by the Tajima clan during the Nanboku-Cho period (1334-1394). As was typical of castles from that era, Mt. Kakusho, the chosen mountain, was terraced to create various baileys, or kuruwa. While defensive structures were constructed at the top and around the mountain, the lord's main living quarters and administrative offices were situated at the mountain's base.

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  • Osaka Castle


    Osaka Castle is a prominent symbol of Osaka City, originally constructed in 1583 by Toyotomi Hideyoshi on the site of the Ishiyama Hongan-ji temple-fortress, which had been the scene of a violent uprising by warrior monks and peasants in the late 16th century. Modeled on Oda Nobunaga’s Azuchi Castle, the original Osaka Castle tenshu (tower keep) featured five visible floors, six interior floors, and two underground basements. The exterior was lacquered black and adorned with gold decorations, including large peony flowers, tigers, birds, and various crests.

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  • Okazaki Castle


    The Shogun, Tokugawa Ieyasu, was born in Okazaki Castle in 1542 during a period of significant civil unrest. At that time, the Tokugawa, then known as the Matsudaira, controlled the rice-rich Mikawa plains of what is now eastern Aichi Prefecture. This fertile region was highly coveted by surrounding warlords. Ieyasu, a shrewd leader and brilliant tactician, managed to maintain and expand his territories. Following in the footsteps of other national unifiers, Oda Nobunaga and Toyotomi Hideyoshi, Ieyasu emerged victorious at the decisive Battle of Sekigahara in 1600. In 1603, he was invested as Shogun, a title he made hereditary, enabling the Tokugawa family to rule Japan for the next 250 years.

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  • Ogaki Castle


    Ogaki Castle, located in Ogaki City, Gifu Prefecture, was originally built around 1500 by Miyakawa Yasusada and named Ushiya Castle due to the Ushiya River serving as a natural moat. The castle was also known as Bi Castle and Kyoroku Castle. The Ogaki region held strategic importance as a transit point between Mino and Omi Provinces, a fact recognized by Saito Dosan, the Viper of Mino. When Oda Nobunaga captured Gifu Castle in 1567, Ogaki Castle came under Oda rule. Both Nobunaga and Toyotomi Hideyoshi understood the strategic significance of the castle. In 1595, Hideyoshi ordered Ito Sukemori to expand the castle and construct the Tenshu keep.

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