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


Before the pandemic you could see a samurai performance at the castle on weekends. Unfortunately, Gyoda city have suspended this event indefinitely. 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 of Oshi Castle – including the new dates from April 2023.
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. Like in November, it is third Saturday of the month and there is no light up in August or January. Moreover in 2023, there is also no light up in July.
Confirmed dates of Oshi Castle Light up in 2023
Since the event began, the event was scheduled by fiscal year, which in Japan is from April to March. However, in 2023, they maybe looking to change that. They released the dates for the months from April 2023 during March, but only until December 2023. Presumably, they are trying to switch the schedule to the more convenient calendar year. There was light up on February 4th and March 4th 2023 as part of the 2022 fiscal year schedule. Here are the confirmed dates for the rest of 2023 (as aforementioned, there is no light up in July or August in 2023):
- April 1st 2023
- May 6th 2023
- June 3rd 2023
- September 2nd 2023
- October 7th 2023 and pink ribbon light up daily
- November 18th 2023
- December 2nd 2023
Moreover, in 2023 for the month of October they will light the castle up pink every night of the month from dusk to 10 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.
Umbrella sky

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! Exclusive information for the 2023 umbrella sky.
Gyoda Floating Castle Festival
The Gyoda Floating Castle Festival, or Gyoda Ukijyo Matsuri, is held every year on the last Saturday and Sunday of July. However, in both 2020 and 2021 they cancelled the festival due to the pandemic. The main part of the festival actually doesn’t take part at the castle, but around Gyoda Station. This sacred rites festival attracts about 55,000 people annually, from all over Saitama and beyond. The Danbe Folk Dance is one of the highlights of this festival. There are also portable shrines, floats, a parade and festival stalls. Furthermore, there is usually a flea market on the day too. The festival is on from late afternoon until about 9 pm at night. Official event website.
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! This year, 2022, the festival is on Sunday November 13th. None of the official websites have been updated with the information yet. You can see general information on the Gyoda City tourism website here.
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.