Mihara Castle was built in the 1560s by Kobayakawa Takakage on islets in the sea, a naval stronghold so surrounded by water it was nicknamed the ‘floating castle’. Land reclamation has long since left it inland, and its keep is gone, but substantial stone ramparts and a moat survive — remarkably, right against Mihara’s shinkansen station, whose platforms were built over part of the site, making this possibly the most accessible castle ruin in Japan. The town connects to the Suigun (naval) heritage of the Seto Inland Sea, where the Murakami clan, often described as pirates, controlled these straits for centuries.
🗓️ At a Glance
| Location | Mihara, Hiroshima |
| Hours | Ruins always accessible |
| Admission | Free |
| Time needed | 30–60 minutes |
| Best time | Spring for cherry blossom on the ramparts |
What to See
- Surviving stone ramparts and moat of a sea castle.
- The unusual sight of ruins abutting a shinkansen station.
- Cherry blossom along the walls in spring.
- Links to the Murakami naval (Suigun) heritage of the Inland Sea.
Combine Your Visit
- Combine with Onomichi a short ride east.
- Pair with a Seto Inland Sea island cruise from the port.
- Read our Hiroshima overview .
Getting There
- By train: Mihara Station (shinkansen and JR) — the ruins adjoin the station.
- On foot: accessible directly from the station concourse.
Tips
This is a quick, free stop rather than a destination in itself — the ruins take half an hour and are literally attached to the station, so they’re ideal to fill a shinkansen connection. Come in spring when cherry trees bloom along the ramparts, and use Mihara as a jumping-off point for Inland Sea island cruises or a trip east to Onomichi.
