There is something quite appealing about trivia of superlatives: the biggest, the longest, the fastest, etc. For me at least, these little factoids tend to accumulate in my memory.
Of course the biggest and best source for such matters is the famous Guinness Book of World Records, and on my recent visit to the island of Shodoshima, the second biggest island in the Seto Inland Sea, I was able to see one natural feature holding a world record, the narrowest navigable strait in the world, Dobuchi Strait.
At first glance on a map Shodoshima appears to be a single island, but is in fact two. The main town of the island is actually spread across two islands, Shodoshima and Maejima. Separating the two is Dobuchi Strait.
The length is about 2.5 kilometers, but the channel narrows to less than ten meters in the middle of the town, less than many rivers. This narrow section has a series of tubular steel arches over it and at night is illuminated. For a 100 yen fee you can go the nearby Town Hall and receive an official certificate commemorating your "crossing" of the strait.
559-2 Ko, Tonosho-cho, Shozu-gun, Kagawa-ken 761-4192
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