Sakhalin island is the largest of the Russian islands. It was known as Karafuto to the Japanese, and is a large and sparsely populated island which was the centre of a long power struggle between Russia/USSR and Japan for control of its large oil and gas resources.

The island is at the far eastern end of Russia. It is located between the Tatar Strait and the Sea of Okhotsk, north of the Japanese island of Hokkaido. With the Kuril Islands, it forms the Sakhalin oblast region. It served as a tsarist prison between 1868 and 1905.

Sakhalin Island is 589 miles (948 km) long from north to south and about 100 miles (160 km) wide, covering 29,500 square miles (76,400 square km). There is a lowland plain in the north, but most of the land is mountainous, reaching an elevation of 5,279 feet (1,609 m) at Mount Lopatin. Vegetation ranges from tundra and stunted forests of birch and willow in the north to dense deciduous forest in the south.

Fishing, mainly of crab, herring, cod, and salmon, is the principal economic activity around the coast. Petroleum and natural-gas extraction in the north, coal mining, and lumbering, including paper production, are the basis of the rest of the economy. The main agricultural activity is livestock raising. The major settlement on the island is Yuzhno-Sakhalinsk, which is the administrative centre for Sakhalin oblast.

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