Name in Japanese: 安土城跡
Pronunciation: azuchi jō ato

The Omi region has many fascinating castle sites, whether original and largely intact castles like Hikone, reconstructions like Nagahama, or evocative sites like Sawayama where the castle was systematically destroyed. But the remains at Azuchi are truly unique and precious for several reasons.

Azuchi Castle was a castle built by Oda Nobunaga on Mt. Azuchi on the eastern shore of Lake Biwa. It was a magnificent structure, with the first large keep designed as a symbol of the owner’s prestige, atop walls all made of stone. The castles built subsequently all followed the pattern of Azuchi.

Today only the walls of the castle remain, as well as the pagoda and gate of Sōken-ji Temple and a mausoleum to Nobunaga. But these remains and their mountaintop location are very impressive and suggestive of the grandeur that once existed here. The nearby Azuchi Castle Archaeological Museum and Nobunaga’s Castle Museum provide highly detailed visual context about the castle and its history, so it’s advisable to spend some time visiting these museums too.

At the time of its construction, the castle was next to a large subsidiary lake of Lake Biwa, which formed part of its defences. Today’s Lake Nishi is all that remains of the lake. The castle keep had six storeys above ground and one storey below. The keep stood about 32 meters high.

For Nobunaga, Azuchi Castle was close enough to the capital at Kyoto to influence matters there without being affected by the disasters and intrigues that frequently occurred. It was also convenient because of the water transportation on Lake Biwa that connected Azuchi to the capital.

The scale and appearance of the castle as described by contemporaries symbolized Nobunaga’s ambition to unify Japan. Nobunaga lived in the keep at the summit of the mountain while his family lived near the main enclosure. His vassals lived on the hillside or in residences at the base of the castle.

Nearby Kannon-ji Castle built by the Rokkaku clan had extensive stone walls topped by defensive buildings, and this advance in castle design was taken to its logical conclusion at Azuchi Castle, where every part was built atop stone walls. One of the innovations of Azuchi was the construction of a central keep on a stone base. Luís Fróis, a Portuguese Jesuit missionary, wrote about the keep in his book, History of Japan:

At the centre is a kind of tower they call the “tenshu”, a more elegant and magnificent structure than our towers. This tower had seven storeys and was built with great architectural skill, both inside and outside. In fact, inside, colourful images are painted covering the entire wall on all sides. On the outside, each storey has a different colour. One is a white wall with the black lacquered windows used in Japan, which is exquisitely beautiful. One storey is red, another is blue, and the top floor is all gold. This keep, like any other mansion, is covered with the most ornate tiles we know. They appear blue and the tiles in the front row have round heads. The roof has a magnificent monster face with a very dignified and elaborate form.

The castle-building technology used here became the model of castles built throughout Japan from the Azuchi-Momoyama period to the early Edo period. This is because the guild of stone masons who built the walls was later contracted to build walls for castles nationwide, so that castles with stone walls spread throughout the country.

The ruins of the castle are distributed over Azuchiyama. A temple gate and three-storied pagoda dating from that time remain within the precincts of Sōken-ji Temple now located on the hillside of the castle. The secondary enclosure also houses the mausoleum of Nobunaga.

Shiga Prefecture has been conducting excavations at Azuchi Castle since 1989. The excavations revealed a major road leading from the southern foot of the mountain to the main enclosure, residences for Hashiba Hideyoshi and Maeda Toshiie beside the road, and a palace imitating the Emperor’s home in the Imperial Palace built in the expectation of a visit from the Emperor.

Another innovation at Azuchi was the method of building the keep. When building a high-rise wooden building such as a tower or pagoda, it’s characteristic of many Japanese buildings to have a central pillar. However, with the keep of Azuchi Castle, there appears to have been no foundation stone for a central pillar. Excavations confirmed that there was no trace of the foundation stone in the centre. Consequently, it’s believed that there was a large atrium space in the middle of the tower spanning several floors.

Although the keeps of castles after Nobunaga’s time followed the pattern of impressive size and beauty as symbols of authority, they weren’t used as the residence of their lords. Rather, they were regarded as the final point of defence and refuge in a sustained attack. However, it’s presumed that Nobunaga lived in his keep, and the lavish interiors reported at the time suggest this.

Despite its strategic and defensible location, the defences of Azuchi Castle are notable for their paucity and apparent weakness. There were very few facilities such as wells required for withstanding long sieges, battlements, and weapon ports. Normally pathways inside castles were made as narrow and winding as possible to prevent the easy passage of attackers, but Azuchi Castle has a straight, six-metre wide avenue leading 180 m from the main gate into the heart of the castle. This suggests that Azuchi Castle was built with a political rather than a military priority. An atrium in the centre of the castle extending from the ground to the fourth floor is believed to have been occupied by a stupa, adding a religious aspect to the expression of political power.

Nobunaga is not known to have been particularly religious. Indeed, his castle is notable for the fact that several Buddhist statues were used to construct the stone steps on the main path, a decision that suggests a very impious mentality. However, Azuchi Castle is unique in having a temple, Sōken-ji, with significant temple buildings within its precincts, including a Niō gate and three-storey pagoda. To reach the keep from the southwestern entrance of the castle, it was necessary to pass through the temple precincts.

History of the castle

In 1576 Oda Nobunaga appointed Niwa Nagahide as general commissioner of construction and began building Azuchi Castle, assisted by his vassals.

In May 1579, Nobunaga moved into the completed keep. Luís Fróis wrote in his book, “The History of Japan”, that lightning struck the main enclosure. To show off his power, Nobunaga gave a gilded folding screen with a painting of Azuchi Castle by Kanō Eitoku to Jesuit missionary Alessandro Valignano. It’s recorded that it was sent to Europe with the Japanese mission to the West and was kept in the Vatican. This would provide decisive evidence showing what Azuchi Castle looked like, but it has yet to be found.

In 1582, there was a reception for Tokugawa Ieyasu, with Akechi Mitsuhide in charge of hospitality. When Nobunaga committed suicide at Honnō-ji Temple, Kyōto on 21 June that year during Mitsuhide’s rebellion, Gamō Katahide was in command of the castle. But after Nobunaga’s suicide, Gamō Katahide and his son Ujisato evacuated Nobunaga’s family from Azuchi to their stronghold Hino Castle. Thereafter, the keep and the main enclosure of Azuchi Castle were destroyed by fire.

There are several records claiming different causes of the fire. After the battle of Yamazaki, the retreating Akechi army led by Akechi Hidemitsu is said to have set the fire. Other records say that Oda Nobukatsu did it because he was feebleminded, that looters set the fire, and that lightning caused it. Which is correct isn’t known.

The remaining secondary enclosure was used by Nobunaga’s descendants for a while, but the castle was abandoned in 1585 when Toyotomi Hidetsugu, the adopted child of Hideyoshi built Hachimanyama Castle.

Visiting the castle site, Nobunaga’s Castle Museum, the nearby Azuchi Castle Archaeological Museum, and the Azuchi Castle Museum near Azuchi Station makes an enjoyable and educational day out.