Oleniy Island is a single island in the Kara Sea

Kara Sea

The Kara Sea is part of the Arctic Ocean north of Siberia. It is separated from the Barents Sea to the west by the Kara Strait and Novaya Zemlya, and the Laptev Sea to the east by the Severnaya Zemlya....

 just a few kilometers offshore, north of the coast of one of the arms of the Gydan Peninsula

Gydan Peninsula

The Gydan Peninsula is a geographical feature of the Siberian coast in the Kara Sea. It is roughly 500 km long and 260 km wide. This wide peninsula lies between the estuaries of the Ob and Yenisei Rivers , which are two of the most important rivers of Russia and the world...

 in North Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

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It is covered with tundra and swamps and it is 53 km in length and its average width is 27 km, having an area of 1197 km². Its latitude is 72° 24' N and the longitude 77° 45' E.

The sea surrounding Oleni Island is covered with pack ice in the winter and there are numerous ice floes even in the summer, so that it is often merged with the Gydan Peninsula in the Siberian mainland, from which is separated by a narrow, only 2 km wide, strait.

Oleni Island belongs to the Yamalo-Nenets Autonomous Okrug

Yamalo-Nenets Autonomous Okrug

Yamalo-Nenets Autonomous Okrug , is a federal subject of Russia . Its administrative center is the town of Salekhard. Population: -Geography and natural history:...

 which is the northern part of the Tyumen Oblast

Tyumen Oblast

Tyumen Oblast is a federal subject of Russia . Its administrative center is the city of Tyumen. The oblast has administrative jurisdiction over two autonomous okrugs—Khanty-Mansi Autonomous Okrug and Yamalo-Nenets Autonomous Okrug. Tyumen is the largest city, with over half a million inhabitants...

 administrative division of the Russian Federation. Oleni is also part of the Great Arctic State Nature Reserve

Great Arctic State Nature Reserve

The Great Arctic State Nature Reserve is a nature reserve in Krasnoyarsk Krai, Russia...

, the largest nature reserve of Russia .

This island is not to be confused with other single islands called "Oleni" or "Oleniy" (Russian: Ostrov Oleniy), one of which is located in the Kara Sea itself, in the Plavnikovyye group

Plavnikovyye Islands

The Plavnikovyye Islands is a group of islands, in the Kara Sea eastern region, off the coast of Siberia.These islands are covered with tundra vegetation and there are many lakes and swamps...

, while the others are in the Barents Sea

Barents Sea

The Barents Sea is a marginal sea of the Arctic Ocean, located north of Norway and Russia. Known in the Middle Ages as the Murman Sea, the sea takes its current name from the Dutch navigator Willem Barents...

 and in the White Sea

White Sea

The White Sea is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is surrounded by Karelia to the west, the Kola Peninsula to the north, and the Kanin Peninsula to the northeast. The whole of the White Sea is under Russian sovereignty and considered to be part of...

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Adjacent islands

• Off Oleniy Island's southwestern tip lie three small islands known as Proklyatyye Islands (Проклятые острова; Proklyatyye ostrova) at 72° 15' N of latitude and 77° 05' E of longitude.
• Rovnyy Island is located close to the mainland coast, a few km east of the Proklyatyye Islands.