Imabari Castle: The Rare Japanese Castle Whose Moat Rises and Falls with the Tide
For travelers: Imabari Castle is in central Imabari, Ehime — the Shikoku gateway to the Shimanami Kaido cycling route. It is about 9 minutes by bus from JR Imabari Station (get off at “Imabari-jo mae”), or a 10-minute walk from Imabari Port. If you are starting or finishing the Shimanami Kaido in Imabari, it makes an easy 1–2 hour stop.
I have loved castles and temples since my school days — I even traveled around Japan’s famous castles on my own as a teenager. Imabari Castle is the one I grew up with, and I have visited it more times than I can count. Let me share some stories about this castle that even many locals don’t know.
One of Japan’s Three Great “Water Castles”
Construction of Imabari Castle began in 1602 under Todo Takatora, a daimyo celebrated as one of Japan’s greatest castle builders, who was rewarded for his service at the Battle of Sekigahara. The castle was completed around 1613.
It was built on what used to be a sandy beach, and together with its vast moat it is counted among Japan’s three great “water castles” (mizujiro). After the Meiji Restoration, most of the castle was dismantled by the government — what genuinely survives from the original is the stone walls.
A Moat That Rises and Falls with the Tide
Here is what makes Imabari Castle truly unusual: the moat is filled with seawater drawn straight from the Seto Inland Sea. Originally there were three rings of moats, and boats could sail right in from the sea.
Because it is seawater, the moat level changes with the tide. At low tide you can almost see the bottom; at high tide the water climbs close to your feet. Rays and even small sharks have been spotted swimming in the moat — it once drew TV crews when the sightings became a local topic. When I was a kid I used to fish here with my rod, though fishing is no longer allowed today.
The “Inubashiri” — a Clue to Building on Sand
Look closely at the base of the stone walls and you will see a flat strip of land about two meters wide running between the moat and the walls. It is called the inubashiri (“dog run”).
Defensively, a wall rising straight out of the moat would be harder to climb, so why leave a ledge? One theory: since the castle stood on soft sand, the ledge was needed to firm up the ground and allow the walls to be stacked high. Takatora was famous for building exceptionally tall stone walls, which makes the theory convincing.
A Keep Born from Imagination
The impressive five-story keep you see today is not the original. In fact, no historical document or photograph confirms that the original castle ever had a keep at all. It is said that Takatora presented his keep to Tokugawa Ieyasu for Tanba-Kameyama Castle, so today’s reconstruction was modeled on old photographs of that castle — a keep recreated from imagination. Knowing this backstory makes the view a little more interesting.
There is one more hidden story: the stone wall used to have a mysterious cave-like hole about two meters deep. Local children — myself included — played in it decades ago. It led nowhere, its purpose is still unknown, and it has since been filled in for safety.
A Shrine Inside the Castle Grounds
In front of the keep entrance stands Fukiage Shrine, where weddings and shichi-go-san (children’s blessing ceremonies) are held. Take a photo looking up at the keep from beside the shrine and you will feel as if you have slipped back into the Edo period.
For locals, the castle is part of everyday life: cherry blossoms in spring, a viewing spot for the summer fireworks festival, and the busiest hatsumode (New Year shrine visit) in town. If you are passing through Imabari, it is well worth a stop.
Visitor Information (as of July 2026)
- Hours: 9:00–17:00 (last entry 16:30)
- Closed: December 29–31
- Admission (keep): Adults 520 yen / Students 260 yen / Under 18 free / Age 65+ 420 yen
- Access: Bus approx. 9 min from JR Imabari Station (“Imabari-jo mae” stop), or 10 min walk from Imabari Port
- Please check the official City of Imabari website for the latest information.
Original article in Japanese: https://starlife2016.net/544.html
