Koka Castles Update: 8 new castles and 3 samurai homes

2023/07/01

Over several more day trips this spring I visited 8 Koka Castles and 3 samurai homes to flesh out the Koka Castles article I started last year. The castles of the Ayukawa Valley (see Kurokawashi Castle) and Tsuchiyama Castle are ones that I really wanted to visit last year but ran out of time. The Ogawa Castle set were recommended by RaymondW and were an unexpected nice surprise. I knew about the castles but they are fairly remote and I didn't prioritize them highly. After all they were a fantastic day out and are great additions to the lore of the Koka Samurai.

Finally I visited the Koka Ninja Village to check out the relocated samurai homes of three Koka samurai. There is unfortunately little information about these homes despite the set being registered as a Japan Cultural Heritage. I had discounted the site as another silly ninja theme park until ART brought it to my attention.

From these travels I made some updates to my Koka Castles feature article by adding new photos, videos of Tsuchiyama Castle and Ogawa Castle and some more details to the text of that page. I'm really pleased how these new additions round out the finished article and expand the area covered by the map. With this update I'm going to shelve the Castles of Koka project for awhile as I work on other projects. There are still some pockets of castles around Koka that I would like to visit in the future, but I'm satisfied with how the story of this region has been told. It seems that Koka City is updating their city history book on the castles of Koka so once it has been published it may spark my interest to visit and document new locations too.

In addition to the castle mapped below, also see these samurai homes:

Fujibayashi Residence Okada Residence Mochizuki Murashima Residence

Ayukawa Castle (Koka) / 鮎河城

Ayukawa Castle is the second castle around the valley of Ayukawa I visited. There is a small park with a stone pillar marking the site of Ayukawa Castle. In documents from the early 1900s it is said that there were foundation stones here for a gate to the castle. They cannot be seen today but the location makes sense for a gate to the manor. Behind this pillar is a large leveled area over looking the valley. This is thought to be the Kurokawa's manor and the mountain behind and to the south of it was the mountaintop castle making this a fortified manor + mountain redoubt castle site. For the mountaintop redoubt there are no trails, just a sign pointing nearly straight up a very steep slope. I made it about 1/2 the way up but it was too steep and wet so for every 3 steps up, I slid 1 step back until I slipped or fell enough times to give up. As only my second castle visit of the day I thought my time was better spent elsewhere and maybe I would return here another day.

Kurokawashi Castle (Koka) / 黒川氏城

Kurokawashi Castle is a FANTASTIC sprawling mountaintop castle. There is a vast network of dry moats, horikiri and embankments built up around the honmaru which also had some great stone walls and an impressive set of stone steps (called gangi) around the inside of the honmaru. On the lower reaches of the mountain before entering the castle you will find several layers of residences of top ranking vassals making it a much bigger and more developed castle than what you would expect for a typical Koka castle out in the middle of the mountains in the borderlands with Iga. With only a few local busses per day that journey out to Kurokawa, it's a challenging castle to visit, but it was well worth the trip. The area is well known for lots of ticks and leeches in the summer months so consider yourself forewarned!

Ogawa Castle (Koka) / 小川城

This one was not even very high on my radar despite putting together the Koka Castles article a year earlier, but RaymondW who visited Ogawa Castle earlier this year (2023) reached out to say that I absolutely had to prioritize this above any other current castle plans because it was so good. Well, the site did not disappoint! The castle offers both stunning views and fantastic castle ruins. It's a brilliantly designed small castle just covering the top of the mountain with with steeps sides and beautifully preserved earthen embankments and trenches. One of the baileys also has some stone wall ruins and the foundation stones of a building.

Just before the main sign and entrance to the castle there is a small trail that cuts down steeply and narrowly from the castle. This trail actually takes you down to a side bailey and continuing down the ridge from here you will find a subsidiary castle called Ogawa Nakanojo Castle. See Ogawa Nakanojo Castle for more details.

Walking up the main road and fire trail to get to Ogawa Castle is fairly easy, but there was one area where there was a lot of noise in the trees above me and a branch fell near me, then another, and another. Looking up, there was some crazed cackling monkey throwing branches down at me. So, if you go, be careful of crazy monkeys too!

Videos

START_WIDGET579072d727ed4fe9-0END_WIDGET

Ogawa Nakanojo Castle (Koka) / 小川中ノ城

You could easily get to the castle if you walk directly from the bus stop, but since I was at the top of the mountain at Ogawa Castle anyway, I did not feel like going back down the route I came and winding around the mountain again, so I elected to take the "trail" from Ogawa Castle down along the ridge to the other side of the mountain and Ogawa Nakanojo Castle.

Just before the main sign and entrance to Ogawa Castle, there is a small trail down to the side bailey of Ogawa Castle. Out the back of this bailey (on the downslope) you may see a small sign that points to Nakanojo Castle. I have read other accounts that say this "trail" is not recommended because it is steep, slippery, overgrown and somewhat dangerous to follow because it is not clearly marked. Actually, I have seen much worse and did not think it was overly difficult, but if you are unsure, don't take your chances. The trail is not really marked and even in winter you have to make some educated guesses at a couple spots to make sure you follow the correct part of the ridge. I used a topographic map app on my phone to make sure that I was heading where I wanted to. There are also maybe two spots where it was very narrow and a bit slippery.

I finally knew I was on the right trail when I found a horikiri trench along the way which was a huge relief. After this relatively small but well preserved horikiri are two more horikiri followed by a huge horikiri. This last one is very steep, slippery and overgrown making it a bit difficult to scale down and back up again, but once you do, you're now at the top of the huge embankment behind the main bailey of Ogawa Nakanojo Castle.

This castle is probably much easier to reach if you start from the town. Just follow the signs from the road side and you can't miss it. On the other hand you will likely miss the horikiri farther up the ridge and miss out out on the castle adventuring enjoyment of having followed the trail that ancient samurai likely used to cross from Ogawa Nishinojo Castle through this castle and up to the mountaintop fort of Ogawa Castle .

Ogawa Nishinojo Castle (Koka) / 小川西ノ城

The last in the Ogawa chain of castles is Ogawa Nishinojo Castle. These castles are generally introduced with Ogawa Castle, but it is most likely that Ogawa Nishinojo Castle was the most important of the three including Ogawa Nakanojo Castle.

I thought this was going to be a quick stop at the castle ruins behind the Seikoji temple on the way to catch the bus, but the castle goes on and on with trenches and earthen embankments marking off layers of baileys around the castle. The baileys are often quite overgrown (even in winter) and hard to see but the trenches certainly make up for it. I missed my bus and would have had to wait over 2 hours for the next one so I called a taxi which was fortunately not as expensive as I anticipated and saved me walking a few km back to the station on weary legs.

Behind the Seikoji Temple, the first bailey you will find looks astonishingly like a typical yakatajiro found in Koka. High earthen embankments and a trench surround a roughly 50m square bailey on the end of the ridge. On the eastern side, is a side bailey with similar embankments and trenches just like other Koka yakatajiro. It is likely that this portion was built by the Tsurumi, the predecessors of the Tarao clan. The Tarao then built out successive layers of baileys along with fortifying Ogawa Nakanojo Castle and Ogawa Castle.

On a side note, while I was at the site a group of workmen came and were clearing bamboo and putting stakes in the ground like they were possibly surveying the site. They kept looking at me funny so I walked up and said hi and asked if they were preserving the site. They kind of laughed and showed me where they were going to build a fence through part of the main bailey and cutting off the second bailey. The purpose was to keep wild boars from running into town from this area. So, be warned, you might not be able to see everything in the future!

Shigaraki is also famous for pottery and particularly those little tanuki statues you see around Japan. Just walking/riding through town you will see them everywhere. Just outside the station is probably the biggest tanuki of them all and the platform inside the station is lined with dozen of the ceramic critters too. Given more time, it might have been a fun town to walk around, not just visiting castles.

Ohkawarashi Castle (Koka) / 大河原氏城

Unfortunately I don't have much to say about this castle. I could not get in. There is a fence all around the base of the castle. There are two gates, both padlocked. I read in another blog that the house by the nearer gate has the keys and is happy to let people in if they stop to ask for permission. I knocked but no one answered the door (or maybe I was ignored). I will try this one another time. In fact if you look closely at the label on Google Maps it says "Temporarily Closed".

Takao Castle (Koka) / 高尾城

Similar to the mountaintop part of Ayukawa Castle, apart from a sign in the middle of the woods behind a temple, there is no decent trail up the steep slope. It's only about half as high as Ayukawa Castle so I managed to scramble up the side of this mountain kind of zigzagging back and forth until I got to the less steep ridge side and worked my way up to the top. Unfortunately, there is a wire fence that runs along the ridge and right across the top of the mountain and through the middle some nice horikiri and baileys. I found one big hole in the fence so I could go back and forth to get in all the pics around the castle. The castle itself is very small. One main bailey, one very small bailey, one side bailey, horikiri on either end and several of tatebori (vertical trenches) dropping down from a nice yokobori (horizontal trench).

Tsuchiyama Castle (Koka) / 土山城　

Tsuchiyama Castle was one of the key Koka castles I did not get to last year. It is a great example of a yakatajiro that starts with a simple square bailey with a large yokobori trench around it. The earthen embankments across the trench add to the defence. The castle also takes advantage of a being on a hill to add some horikiri trenches out rear entrance.

Of particular interest are 2 well defined and preserved square umadashi entrances marked as baileys II and V on the map. No other Koka castles have umadashi and it would have been ahead of its time to have these in Omi in the middle of the Sengoku Period. It seems likely that Hideyoshi forces may have fortified the castle and camped here around the time of the Battle of Komaki and Nagakute.