Oshi Castle Ruins are located in Gyoda City in Eastern Saitama Prefecture. Nicknamed “the floating castle”, and sometimes “Turtle Castle”, due to its position on elevated land surrounded by water, the story of the castle is particularly famous. In its day, the castle was considered one of Kanto’s seven strongholds. The Narita clan built Oshi Castle. It was completed in 1479. But what the castle is most famous for is withstanding a siege against incredible odds. There is even a movie about the Siege of Oshi (Castle), Nobuo no Shiro, which was named The Floating Castle in English. There is plenty online in English about the history of this castle, but I want to introduce contemporary Oshi Castle…
Present day Oshi Castle
Oshi castle is the pride and joy of Gyoda City. What remains of it in modern day Gyoda is the three story turret “Gosankai Yagura”, the foundations of the original castle, “Korai” castle gate and a moat. There are carp in the moat river. In addition, there is a very small park around the castle. The three story turret was reconstructed on the grounds in 1988 to function as the Gyoda City Museum. There is a great view from the top floor of the tower. The museum costs 200 yen to enter, but you can roam around the grounds freely.
Monthly events at the castle
Until March 31st 2026 there is a real mystery solving game, “The Mystery Sleeping in Oshi Castle”, on the castle grounds. However, you have to buy the kit for the game at the museum, which is closed on Mondays. A kit costs 600 yen. It takes about an hour to 90 minutes to finish the game. Official event page.
Before the pandemic you could see a samurai performance at the castle on weekends. They suspended it during the pandemic, but its back on occasionally now. However, even during the pandemic, there is a monthly event on at the castle. “Gyoda Hanachozu week” is actually two weeks long. Hanachozu are the water fonts with flowers in them. Playing on the nickname “floating castle”, the castle displays floating flowers during hanachozu week. Moreover, they light up the castle and the floating flowers for one night only during that period for an event called “Light of Hope“. You can see the hanachozu event post here. But this post includes information for the light up at Oshi Castle:
Light up of Oshi Castle
Above, Oshi Castle lit up at night, Saturday November 19th 2022. I also took the featured photo at the top of the post on November 19th 2022. I’ve included an Instagram video below too. They also light up Gyoda Hachiman Shrine and Sakitama Shrine. They generally light it up on the first Saturday of the month, there are exceptions though. Unfortunately in 2026 they have once again reduced the number of times the light up is on. It will only be on a total of six times in 2026.
Confirmed dates of Oshi Castle Light up in 2026
As above, in 2026 it is only on six times (the least number of times to date);
- March 7th
- April 4th
- May 2nd
- October 3rd
- November 7th
- December 5th
In addition, the castle is lit up pink every night of the month of October, for pink ribbon month, from dusk to 10 pm. And for the November and December light up usually has projection mapping too, but that has not yet been confirmed for 2026. For the October 3rd event, there will also be a “Heritage Marche” on the day, from 12 noon to 7 pm.
Seasonal Events at the Castle Ruins
Cherry blossoms
The Oshi Castle remains look particularly pretty in spring when the cherry blossoms are in bloom. There aren’t that many cherry blossoms directly around the castle, but it is possible in about three different spots, to get a photo of cherry blossom backdropped by the castle. Moreover, a short walk away, there is a famous sakura spot at Gyoda Suijo Park.
Koinobori
You can usually see ‘koinobori’ carp streamers displayed on the lead up to, and during, Golden Week (end of April / early May).
Umbrella sky, Wind Chimes & Mist
There are floating umbrellas at the floating castle in the summer! In 2023, they went up much earlier than normal, in May. In 2022 and 2021 it was July! Between 2022 and 2024 it was mid June, but in 2026 it is back to a July start. Exclusive information for the 2026 umbrella sky, with two new features – wind chimes and (on weekends only) a sea of mist.
Gyoda Floating Castle Festival
Chrysanthemum Exhibition
Each year in Autumn there is a display of Chrysanthemum in front of Gyoda City Local Museum. In 2024 you can see it from Wednesday October 30th to Sunday November 10th.
Gyoda Industry and Oshi Castle Era Festival
The Gyoda Industry and Oshi Castle Era festival or Gyoda Kogyo / Oshi Jyo Jidai Matsuri takes place around the middle of November annually. The highlight of the festival for many is the parade of ‘samurai’ and a musket shooting performance! There are also live performances and a bazaar, among other events. This year, 2024, the festival is on Sunday November 17th from 10 am to 4 pm. Official event page.
Nobuo no Shiro
Oshi Castle became even more popular within Japan thanks to the 2012 movie “Nobuo no Shiro”. The movie is called The Floating Castle in English. It tells the story of the Siege of Oshi. The story of the siege is very famous in Japan. Because against great odds, the Oshi villagers, about 500 of them, defended the castle against 20,000 samurai. Moreover, the movie was adapted from the novel of the same name and is based on historic facts. You can see why the people of Gyoda are so proud of Oshi Castle.
Information
Keep an eye out for the Oshi Castle manhole cover art – with chrysanthemum, the flower of Gyoda – all around the city.
Address: 17-23 Honmaru, Gyoda, Saitama 361-0052
Phone: +81485545911
Hours: The grounds are open 24 hours, but the museum within the turret, is open from 9 am to 4.30 pm (last entry at 4 pm). The museum is closed on Mondays and the fourth Friday of the month.
Cost: Free to roam the grounds, admire the hanachozu, but 200 yen into the museum for adults. High school students and University students are charged 100 yen and it is 50 yen for a child over 6 years old.
Access
The Oshi Castle ruins are about a 15 minute walk from Gyodashi Station on the Chichibu Railway line. If you are using the JR Takasaki line you can get a bus from Gyoda station. Take a city loop bus from the station and get off at Oshi Castle Ruins. They announce the bus stop stop name in English too. It takes about 20 to 25 minutes from Gyoda station to the ruins on that bus.
If you come by car, there is free parking on the grounds.
First published January 17th 2022 at 12.00 pm. Completely revamped and updated with new photos and information, first in August 2022 and again in November 2022.