Discover the extraordinary underwater world of the Kanmon Straits at the Kaikyokan — an immersive aquarium and maritime museum where the star residents are the fugu (pufferfish) that made this region world-famous, alongside a captivating live window onto the world's busiest waterway.
What to expect
The museum pairs a world-class aquarium — home to dozens of fugu species, the pufferfish that defines this region's culinary identity — with fascinating exhibits on the history, ecology, and maritime commerce of the Kanmon Straits. The highlight is the underground observation corridor with its direct window onto the straits floor, where the tidal current creates a mesmerising natural spectacle. Interactive displays cover the geology of the strait, the famous Battle of Dan-no-ura fought in these waters in 1185, and the marine ecosystems beneath the ship traffic above.
Good to know
A 5-minute walk from Mojiko Station and the pier. Combine with the Mojiko Retro 3-Facility Pass for discounted entry alongside the Observation Gallery and Kaikyo Plaza. Allow 60–90 minutes for a comfortable visit. The museum is air-conditioned — ideal for hot summer port days.
More to do in Moji (Kanmon Straits)
- Shimonoseki & Mojiko Retro: Private Full-Day Licensed Guide Tour
- Kanmon Straits Twilight Cruise: Private Boat Through Japan's Busiest Channel
- Mojiko Retro District: Meiji Architecture & Baked Curry Masterclass Walk
- Mojiko Retro Observation Gallery: 103m Panorama of the Kanmon Straits
- Karato Fish Market & Shimonoseki Fugu Experience: Japan's Pufferfish Capital