186.Kaneda Castle Patr1

Kaneda Castle was one of the ancient mountain castles in western Japan. They were built by the Imperial Court after the Battle of Baekgang, Korea in 663. Kaneda Castle was at the foremost line against possible invasions from the alliance of Tang and Silla. This was because it was located in Tsushima Island, only about 50km away from Korea.

Location and History

One of Ancient Maintain Castles

Kaneda Castle was one of the ancient mountain castles in western Japan. They were built by the Imperial Court after the Battle of Baekgang, Korea in 663. Japan tried to help Baekje, but was beaten by the Tang and Silla alliance. Emperor Tenchi was scared of invasions from the alliance, so he ordered these castles’ constructions. Kaneda Castle was at the foremost line against the alliance because it was located in Tsushima Island, only about 50km away from Korea.

The locations of the major ancient mountain castles

The map about the Battle of Baekgang (licensed by Samhanin via Wikimedia Commons)

These castles are also called Korean style mountain castles which were established in Korea and brought to Japan with the instructions from the refugees from Baekje. There had been many battles in ancient Korea (part of present day North and South Korea) due to invasions from China and the internal conflict with three countries, Baekje, Silla and Goguryeo. The style involves surrounding the whole mountain by stone walls or earthen walls, which was very different from that of Japanese castles that would be later established. If people in Korea at that time were attacked by enemies, they would escape to their mountain castle, wait for the enemies’ supply to run out and counterattack the enemies. This style was applied to Japan to immediately prepare for possible invasions from the alliance.

The diorama of Kaneda Castle Ruins, exhibited by the sightseeing information center Fureaidokoro Tsushima

Stone Walls mostly surround Mountain

The Imperial Court built Mizuki in 664 as the 1st ancient mountain castle. After that, it also built Ono and Kii Castles in 665, and then, Takayasu, Yashima and Kaneda Castles in 667, according to Nihon-shoki, the oldest official chronicles of Japan. It is thought that nearly 30 ancient mountain castles, including recorded and non-recorded ones, were built along the estimated routes of the invasions around the northern Kyushu Region and Seto Inland Sea. The Imperial Court also drafted soldiers from eastern Japan, who would be called Sakimori, and sent them to the northern Kyushu Region to protect and monitor this area. The fire-signal system was also developed in the region to rapidly inform the signs of what happened.

The ruins of Mizuki
The ruins of Ono Castle
The ruins of Kii Castle

Kaneda Castle was built on Joyama Mountain facing Aso Bay in the central part of Tsushima Island. The castle was about 15km away to the north from the provincial capital of Tsushima, near the current Izuhara Port. This was probably because the usage of the castle would follow that of the mountain castles in Korea like a shelter. Its perimeter was about 2.2km, which was mostly covered with stone walls, in contrast to other ancient mountain castles like Ki-no-jo, mostly surrounded by earthen walls. The northern and western sides of the castle were along the steep ridges of the mountain, which were naturally very defensive. On the other hand, the southern side faced the valley which would be the entrance to the castle and the eastern side was beside the bay. That’s why several gates were built and the stone walls were higher on these sides. It is thought that there were no office buildings and no warehouses, but only buildings like barracks the Sakimori soldiers used inside the castle, according to the results of excavations.

The aerial photo around the castle

The Aso Bay
The stone walls of Kaneda Castle (the southeast stone fortress)
The earthen walls of Ki-no-jo

The relief map around the castle

Castle is shortly abandoned because of Stable Diplomatic Relations

Meanwhile, the diplomatic negotiations with foreign countries continued. For, example, Tang and Goguryeo started to fight with each other in 666. Both countries asked Japan for help. While Emperor Tenchi moved the capital from Asuka in Nara to Otsu, more interior than Asuka in 667 and made the first national census in 670 probably to prepare for the next war. The tension between Japan and Tang reached its peak after Tang defeated Goguryeo in 668. It is said that Tang actually planned to invade Japan then. However, the plan was canceled as Tang and Silla battled each other in 670. The battle resulted in Silla repelling Tang and the unification of Korea Peninsula in 676. The next emperor, Tenmu, also made friendly relations with Silla, which meant the serious threat to Japan had gone.

The ruins of the imperial palace of Otsu (licensed by Saigen Jiro via Wikimedia Commons)

As a result, there would be no need for maintaining all the ancient mountain castles. Many of them including Kaneda Castle were repaired or improved by the end of the 7th Century. However, it is thought that Kaneda Castle was abandoned at the beginning of the 8th Century. Manyoshu, the oldest anthology of Japan, which was first published in the late 8th Century, contains a Tanka poem created by a Sakimori soldier who was in charge of Tsushima Island. Interestingly, this Tanka was published nearly a century after the castle was active. The life of this great castle was only 30 to 40 years.

The ruins of Kaneda Castle (the first gate)

To be continued in “Kaneda Castle Part2”

182.水城~Mizuki

緑の防衛ラインが今だにくっきりと残っています。
The green defense line still stands prominently.

立地と歴史~Location and History

大宰府を守る防衛線~Difense Line to protect Dazaifu

水城は、663年の朝鮮での白村江の戦いで日本が唐と新羅の連合軍に敗れた直後、国が初めて作った本格的な軍事施設です。それは、連合軍の侵攻から古代日本の地方政府であった「大宰府」を守るための防衛ラインでした。つくられたのは664年で、大野麹智基肄などの古代山城と呼ばれた西日本の軍事施設より以前のことでした。そのため水城は、日本の城のうちの一つとみなされています(その名前自体が水の城です)。
Mizuki was the first national full-scale military facility built immediately after Japan was beaten by the ally of Tang and Silla in the Battle of Baekgang, Korea in 663. It was a defense line to protect the ancient Japanese local government, “Dazaifu” in Kyushu Island from the ally’s invasion. It was first built in 664 before other military facilities in western Japan called ancient mountain castles such as Ono, Kikuchi, and Kii. That’s why Mizuki is regarded as one of the castles of Japan (The name means Water Castle in Japanese).

白村江の戦いの図~The map about the Battle of Baekgang(licensed by Samhanin via Wikimedia Commons)

戦略的な設計~Strategic Design

この防衛ラインは東は四王寺山の麓と、西にあるもう一つの丘との間に設けられており、福岡平野では最も狭い部分に当たり、大宰府政庁の北にありました。幅80m、高さ10mの土塁が1.2kmに渡っていました。そして両側に水堀がありました。この地域の地盤が弱かったので、土塁は丈夫な枝葉の基礎の上に設置されました。この構成により土塁を強固にする方法は「敷そだ」と呼ばれました。土塁自体を強固にするためには、土を突き固める版築という方法が採用されました。水堀は、土塁の下を通る木樋によってつながっていました。その水は内側の堀から外側の堀に流れていました。
The defense line is located between the foot of Shioji-yama mountain on the east and another hill on the west, which is the narrowest part of the Fukuoka Plain, and the north of Dazaifu government. It consisted of earthen walls that were 1.2km long, 80m wide and 10m high. It was surrounded by water moats on both sides. As the earth was weak in that area so the walls were laid on a foundation of strong branches. And this method of making the structure or wall strong was called “Sikisoda”. To make the walls sturdy the workers use to ram soil on the wall and this method was called Rammed earth. The water moats were connected under the earthen walls through wooden water pipes. The water flowed from the inside into the outside part of the moat.

城の位置~The location of the castle

水城に残る土塁~The remaining earthen walls of Mizuki
復元された木樋~The restored wooden water pipe(licensed by Saigen Jiro via Wikimedia Commons)

土塁の幅は戦略的に設計されており、守備兵の矢は土塁の高い位置から放たれ外側に届くが、敵の矢は外側の低い位置から放たれ、内側には届かないようになっていました。歴史家は、朝鮮からの亡命者がこれを設計したと推定しています。
Its width was strategically designed so that when the defender’s arrows shot from the upper part of the wall, it could reach outside but when the enemy shot from lower part outside the moat, it couldn’t reach inside. Historians speculate that this method was designed by Korean refugees.

水城の構造模型~The model of Mizuki(水城館~Mizuki Site Exhibition Hall

交通の要地~Important Point for Traffic

このラインには2つの門があり、それぞれ官道が通っていました。一つは東門から博多港の方に伸びており、もう一つは西門から鴻臚館と呼ばれた中国や朝鮮からの人々をもてなす迎賓館の方に伸びていました。大宰府政庁の出入口としても使われており、この地域の交通や旅行者の出入りを監視していました。
The line had two gates for two government-run roads. One of them went through the East Gate to Hakata Port, and the other went through the West Gate to the guest house called Kouro-kan that was used to host people from China and Korea. It was also used as the entrance of Dazaifu government, and it checked transportation and passengers in and out of that region.

古代官道の推定ルート~The estimated routes of the government-run roads(現地説明板より~From the signboard at the site)

幸いにも、連合軍は日本を攻撃しませんでした。水城は大宰府政庁の道しるべとなりました。多くの人々が訪問客の出迎えや見送りのためにここを使ったのです。
Fortunately, the ally did not attack Japan. Mizuki became a landmark of Dazaifu government. Many people used it to welcome or say good-bye to visitors.

現在水城を通り抜ける道路~The present road through Mizuki

特徴~Features

現在、この辺りを通る人たちの多くは、水城跡をはっきりと見ることができます。なぜなら、この遺跡は緑地帯のように今だにこの一帯に横たわっていて、公道、高速道路、鉄道といった多くの現代の交通網もまたこの遺跡を横切っているからです。この遺跡は緑の林に覆われた土塁として残っているのです。素晴らしいことだと思いませんか。
Now, many people who go through the area around the ruins of Mizuki can clearly see them. This is because the ruins still lay across the area like a green belt, and a lot of modern transportation such as public roads, Expressways and Railways, also go across the ruins. The ruins remain as earthen walls covered with green forests. Isn’t that fantastic?

城周辺の航空写真~The aerial photo of around the castle

土塁周辺を歩く~Waking around Earthen Walls

この土塁からは既に水堀は失われています。そして、ところどころ現代の交通網により寸断されてしまってもいます。しかしながら、土塁の周辺を歩いてみれば、少なくとも高さが違っている構造になっていることはわかると思います。また、JR鹿児島本線により寸断されている箇所では、どのように土塁が積み上げられているかがわかります。The earthen walls have already lost their water moats, and the walls are partly destroyed by the modern transportation. However, when you walk around the walls, you can at least see the different levels of the structure. You can also see how the walls were rammed at the cross section of the walls which are cut through by the JR Kagoshima Line.

低くなっている土塁の外側~The lower outside of the earthen walls
高くなっている土塁の内側~The higher inside of the earthen walls
土塁の断面~The cross section of the walls(taken by ヘンリー3世 from photoAC)

東門周辺~Around East Gate

東門跡では、国道112号線がかつての古代官道のように遺跡を通り抜けています。後になって人々は門が元々あった場所に石碑を作って設置しました。門の礎石はまだ残っていて、遺跡を見に来た人であれば、すぐ見つけられます。また、水城館という展示施設があって、水城の歴史や使われている技術を学ぶことができます。この辺りは土塁の東端に当たるため、山裾の方に登って行って、遺跡の全景を見ることもできます。
At the ruins of the East Gate, the National Route 112 goes through the ruins like the ancient government road. Later on, people made and placed stone structures where the gates use to stand originally. The cornerstones of the gate still exists and anybody who visits the ruins can see them . You can also visit the guest house called Mizuki-kan which exhibits the history and technology of the ruins. The area is near the eastern edge of the earthen walls, so you can walk up to the foot of the mountain and have the whole view of the ruins.

国道112号線~The National Route 112
石碑と土塁~The stone structure and earthen walls
東門の礎石~The cornerstones of the East Gate
水城館~Mizuki-kan
水城の全景~A full view of Mizuki

西門周辺~Around West Gate

西門の跡については、ここもまた地方道路により壊されてしまっています。発掘によれば、西門は3回立て直されています。門はその時代ごとの要請によって、機能が違っており、外交関係が悪いときは関門として機能し、関係がよくなると飾り立てられていたようです。
At the ruins of the West Gate, they are also destroyed by a local road. The excavation found that the gate had been rebuilt three times. It was a functional gate that was built as per requirement. The gate served as a barrier when foreign relations were bad. However, when relations were good it was more decorative.

西門の想像図~The imaginary drawing of the West Gate(大野城市Websiteより引用)

その後~Later History

中世の13世紀頃、門は失われていました。しかし武士たちはモンゴル襲来のときに跡地を陣地として使用したようです。江戸時代には東側の官道は日田街道となり、多くの人々が往来しました。人々は水城を著名は遺跡として認識していました。1953年には国の特別史跡に指定されます。
Around the 13th century of the Middle Ages, the gates had been lost, but warriors seemed to use the ruins as a position against the Mongol Invasion. In the Edo Period, the eastern government road was being turned into Hita Road many people used. The people had already recognized Mizuki as famous ruins. The ruins have been designated as a Special National Historic Site since 1953.

水城関跡、筑前名勝画譜より、江戸時代、国立公文書館蔵~The ruins of Mizuki, from The Picture Book of Famous Sights in Chikuzen Province, in the Edo Period, owned by National Archives of Japan(水城館展示、An exhibition of Mizuki-kan)

私の感想~My Impression

白村江の戦いは、日本の歴史において重要な出来事でした。水城跡は、多くの人々が近くを通るだけで目にすることができる、とても分かりやすい遺跡だと思うのです。歴史の知識があれば、水城がなぜ築かれたか多分わかるでしょう。知識がなくとも、遺跡を見てもっと知りたいと思うかもしれません。水城が永久に守られることを切に望みます。
The battle of baekgang is an important event in the history of Japan. I think that the ruins of Mizuki are very easy to understand for many people, because they can have many chances to see the ruins when they pass by. If they have the knowledge of history, they will probably understand why Mizuki was built easily. Even if not, they may want to learn more about the ruins seeing them. I really hope that Mizuki will be kept forever.

土塁と水城館~The earthen walls and Mizuki-kan

ここに行くには~How to get There

東門跡に行くには:
車では、九州自動車道の大宰府ICから数分のところです。展示施設に駐車場があります。
電車の場合は、西鉄天神大牟田線の下大利駅から歩いて約20分です。
西門跡に行くには:
車では、九州自動車道の大宰府ICから約10分かかります。水城ゆめ広場に駐車場があります。
電車の場合は、JR鹿児島本線の水城駅から歩いて数分のところです。
To the ruins of the East Gate:
By car, it takes few minutes from the Dazaifu IC on Kyushu Expressway. The guest house offers a parking lot.
By train, it takes about 20 minutes on foot from Shimo-ori Station on Nishitetsu Tenjin-Omuta Line.
To the ruins of the West Gate:
By car, it takes about 10 minutes from the Dazaifu IC on Kyushu Expressway.
Mizuki-Yumehiroba Park offers a parking lot.
By train, it takes few minutes on foot from Mizuki Station on JR Kagoshima Line.

リンク、参考情報~Links and References

水城跡、大野城市(Onojo City Website)
水城館、古都大宰府保存協会(Japanese Association Website)