The , also called the Kii Strait, is a

strait A strait is a water body connecting two seas or water basins. The surface water is, for the most part, at the same elevation on both sides and flows through the strait in both directions, even though the topography generally constricts the ...

separating the Japanese island of

Shikoku is the smallest of the List of islands of Japan#Main islands, four main islands of Japan. It is long and between at its widest. It has a population of 3.8 million, the least populated of Japan's four main islands. It is south of Honshu ...

from the

Kii Peninsula The is the largest peninsula on the island of Honshū in Japan and is located within the Kansai region. It is named after the ancient Kii Province. The peninsula has long been a sacred place in Buddhism, Shinto, and Shugendo, and many people wou ...

on the main island of

Honshū , historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the seventh-largest island in the world, and the second-most populous after the Indonesian ...

. This strait connects the Inland Sea with the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

. The name of the strait derives from

Kii Province , or , was a province of Japan in the part of Honshū that is today Wakayama Prefecture, as well as the southern part of Mie Prefecture. Nussbaum, Louis-Frédéric. (2005). "''Kii''" in . Kii bordered Ise, Izumi, Kawachi, Shima, and Yamato Pro ...

, a former province on the Kii Peninsula. The strait is surrounded by

Tokushima Prefecture is a Prefectures of Japan, prefecture of Japan located on the island of Shikoku. Tokushima Prefecture has a population of 682,439 (1 February 2025) and has a geographic area of 4,146 Square kilometre, km2 (1,601 sq mi). Tokushima Prefecture b ...

on Shikoku,

Wakayama Prefecture is a prefecture of Japan located in the Kansai region of Honshu. Wakayama Prefecture has a population of 876,030 () and a geographic area of . Wakayama Prefecture borders Osaka Prefecture to the north, and Mie Prefecture and Nara Prefecture to ...

on Honshū, and the southern coast of Awaji Island in

Hyōgo Prefecture is a Prefectures of Japan, prefecture of Japan located in the Kansai region of Honshu. Hyōgo Prefecture has a population of 5,469,762 () and a geographic area of . Hyōgo Prefecture borders Kyoto Prefecture to the east, Osaka Prefecture to th ...

. It is connected to

Osaka Bay Osaka Bay (大阪湾 ''Ōsaka-wan'' ) is a bay in western Japan. As an eastern part of the Seto Inland Sea, it is separated from the Pacific Ocean by the Kii Channel and from the neighbor western part of the Inland Sea by the Akashi Strait. I ...

via the Kitan Strait and to Harima Nada (the eastern part of the Inland Sea) by the Naruto Strait. Western maps from the 19th century also refer to this waterway as the Linschoten Strait.Taylor, Bayard. ''Japan, In Our Day''. New York: Scribner, Armstrong, and Co, 1872. Preface map.

References

Straits of Japan Bodies of water of Hyōgo Prefecture {{Wakayama-geo-stub