A thrilling ride along the racing currents of Kurushima Straits. Discover the area’s history and sites, including the enormous shipbuilding works!
The Shimanami Kaido road, which connects Onomichi City in Honshu to Imabari city on Shikoku island, crosses over several islands in the Seto Inland Sea, Oshima island being the last one at the southern end of the road. The Kurushima Strait exists between Oshima island and Shikoku, and is well-known for having one of the three fastest currents in Japan. Rapid swells and a complex terrain create powerful whirlpools that swirl across the Strait. We experienced this thrilling natural adventure on a Kurushima Strait Boat!
To the ticket booth
We first visited a roadside rest stop, Michi no Eki Yoshiumi Iki-Iki Kan, before going ahead to the boat. Here, we purchased our boat tickets and moved on to the Shimoda Water Port where the boat would depart. It takes 3~5 minutes by foot to get to the port from the Yoshiumi Iki-Iki Kan. Please remember to buy tickets ahead of time. The crew will check your ticket while embarking, and then you’re ready to set sail!
Looking up at the Great Kurushima Strait Bridge
Soon after departure, the boat sailed just below the Great Kurushima Strait Bridge. Looking up at the bridge from underneath, and at such a unique angle, was certainly a privilege for the boat tour passengers. This majestic bridge is not only the largest bridge in Shimanami Kaido but the world’s first triple suspension bridge. We were stunned by the size of the "anchorage" that secures the cables of the bridge. This vast concrete block is about 90 meters high, which its 60-meter part exposed above the water.
The most powerful current occurs at full moon or new moon day
There are a few spots where we could see the whirlpools closely. The boat turned off the engine at these spots so passengers could feel their intensity. (The boat may not be able to stop due to currents or weather conditions.)
Another great site is the "sea spouts” appearing as if seawater is rising out from underneath due to the complex sea bottom terrain.
The most powerful tidal current is seen during the full moon or on new moon day. Despite the natural phenomenon, this is pretty predictable as the tide is so in sync with the moon calendar.
The islands associates with the Murakami Pirates.
This area has a significant history as the headquarters of the Murakami Pirates. These most powerful Japanese pirates prospered during the Muromachi and Sengoku period. The headquarters’ island, Kurushima, is actually a tiny island with a circumference of only 850m. A shrine near the port and facing out to sea allows for those on the boat to offer prayers to the Kurushima Yachihoko Shrine. The Pirates’ fortress was built around the neighboring islands too. The smooth trail, Musha-Bashiri, meaning warrior track, still remains on the uninhabited island of Mushijima, revealing how they prepared for combat there.
Shipyard
More things to see! Shipbuilding is a vital industry in Imabari City. This area is a crucial point of maritime transportation, and 700~800 ships run through here every day. We could see from our boat the many shipbuilding factories and docks lined up along the coast. They looked like giant buildings rising out from the sea. We were overwhelmed by their enormous size as we approached the construction and ship reparation site.