Doudo Castle (Mikawa)


MikawaDoudojou (6).JPG


Dōdojō was constructed in 1533 by the Aoyama Clan after they were granted territory in the area by their lord, Matsudaira Kiyoyasu. The lord of the castle in the Sengoku period was Aoyama Tadamon who fought in battles against the Takeda Clan, as well as at the Battle of Okehazama (1560) and the Battle of Azukisaka (1564). During the Mikkawa-Ikkō-Ikki revolt (from 1562) he fought for Tokugawa Ieyasu and helped defend Okazakijō. Fighting against the Takeda when they launched their invasion of Mikawa via Asukejō (from 1571), Tadamon thwarted them by constructing a series of palisades. He also later repulsed them at Shinpukuji, to the north of Dōdojō, but was killed in battle by gunshot. He was succeeded by his son, Aoyama Tadanari. Dōdojō was abandoned in 1590 when Tokugawa Ieyasu moved to Kantō. Aoyama served as the tutor to Tokugawa Hidetada, the second shogun, and became magistrate of Edo with a personal fief in Sagami; his son, Aoyama Tadatoshi, served Tokugawa Iemitsu as a lieutenant.

Visit Notes

Dōdojō is a hilltop fort site in Okazaki Municipality. No ruins remain but the hill is still wooded and there is an Edo period cenotaph for the former castle lord.

I was excited to visit this site mostly because of the name. The double ‘hundred’ pictograms piqued my interest. Then I saw a transcription of the reading as ‘Dodo’ and became elated. Imagine visiting Dodo Castle (even if there was nothing to see now). I was pumped. However, cruelly, the arbitrary chaos of Japanese readings tarred this prize, as the actual reading proved to be ‘Dōdo (どうど)’ which is completely different – as we all know. Nastily, even though the kanji repeats, the reading on the second character is different. 々 is used to indicate a repetition of the proceeding character (it’s meant as a shorthand even though 人々 has more strokes than 人人), but it does not guarantee a repetition of the sound (you would need ゝ for that). The truth is that any reading can be applied to any character in Japanese. Place names can be particularly obscure and obtuse, and the only solace is in convention.

Dōdojō today is developed over with housing but there is a shaded forested area on the hillside beneath the castle site. Here there is a genbu (‘black tortoise’) monument. This is the main attraction of the site, as it serves as a large cenotaph for Aoyama Tadamon who fought for the Matsudaira against the Takeda. Aoyama Tadataka, the lord of Sasayama Domain, erected it in 1770.

I entered the site after cycling to the end of a new concrete strip of what looked to be part of a retaining wall. Old stairs lead down the hill, but I didn’t go down them. Later I checked for where the actual entrance to the site was after previously cycling past a part abutting the road with a chain-link fence without an opening. I can find no opening between houses, and the entrance appears to be blocked. Satellite images tell the story of large old residences surrounding the hill being replaced by pokey modern box-like housing.


Castle Profile
English Name Doudo Castle (Mikawa)
Japanese Name 三河百々城
Founder Aoyama Clan
Year Founded 1533
Castle Type Hilltop
Castle Condition Ruins only
Historical Period Pre Edo Period
Visitor Information
Access Nearest station is Daimon Station on the Aichi Loop Line; 32 minute walk
Visitor Information Access Limited
Time Required 20 minutes
Website (%E4%B8%89%E6%B2%B3%E5%9B%BD)
Location Okazaki, Aichi Prefecture
Coordinates 34° 59' 19.68" N, 137° 10' 27.26" E
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Added to Jcastle 2023
Contributor ART
Admin Year Visited Viewer Contributed
Friends of JCastle
Jōkaku Hōrōki
Umoreta Kojō
Jōkaku Shashin Kiroku
Aichi Shiro
Shiro Iku

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