Sōya Strait, or La Pérouse Strait, is a strait dividing the southern part of the Russian island of Sakhalin from the northern part of the Japanese island of Hokkaidō, and connecting the Sea of Japan on the west with the Sea of Okhotsk on the east. It serves as a maritime boundary between Japan and Russia.

Between 1905 and 1945 the southern part of Sakhalin was Japanese territory, known as Karafuto. The territory was won by Japan in the Russo-Japanese War of 1905 and returned to Russia following World War II. Several memorials commemorate the flight of Japanese citizens from Karafuto to Hokkaido as the Russians reclaimed their lost territory.

Soya Strait is also named after Jean-François de Galaup, compte de Lapérouse, who explored it in 1787. It is known by both names, but in Japan it is best known as Soya Strait.

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