Beyond Takamatsu’s cityscape are the Sanuki Mountains. Look seaward and you will see islands pockmarking the waters.

While they seem calm, these waters actually hold the fastest tidal currents in all Japan.
In fact, Japan’s big three tidal straits – Naruto, Kurushima, and Kanmon – are all here in the Inland Sea. The reason for their vigorous currents? The Inland Sea’s complex terrain.

When massive amounts of seawater enter the shallow straits, the speed of the currents rises, up to 18 kilometers per hour. At the Naruto Strait the tides swirl, creating white foaming whirlpools that make the roiling sea feel alive and breathing

The tide carries nutrients and oxygen from the river to the living creatures in the Inland Sea. The speed shaves away the sea bottom, rendering it uneven in places. This creates more spaces for fish to dwell.
None of this marine bounty is by accident – it is birthed by Nature’s design.

Takamatsu Port was once a crucial port of call for ships sailing the Inland Sea. During the Matsudaira Clan’s reign over the city in the Edo Period, the sea-facing city flourished as a castle town. Tamamo Castle was built here. A rare “sea castle,” it is enclosed by a seawater moat. Modernity brought railroads to Takamatsu, transforming it into the bustling gateway to Shikoku. Nowadays, the port region remains the largest in Shikoku, featuring the Anabuki Arena, as well as large shopping malls and hotels as far as the eye can see. Shōdoshima and the other islands are connected by various ferries, and even large-scale cruise ships from overseas dock at the port. It is a vibrant sight.

Riding this ferry right now, you are an extension of a “current” of goods and people, flowing throughout this region for centuries.

Anyone who’s sailed before has wondered what lies beyond the horizon.
So let the currents weave you like thread upon the fabric of an ocean that has covered mountains, and enjoy the journey.