Ōshima Strait
Japan
The Ōshima Strait (Ōshima kaikyō) is a strait between the islands of Amami Ōshima and Kakeromajima in Japan. It is part of the Amami Guntō National Park. From the western most side to the eastern most side of the strait, the strait measures 17.5 miles (28.2 km) long.
Data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).