Beryozovye Islands alternatively spelled Berezovye Islands, is an island group in Leningrad Oblast

Leningrad Oblast

Leningrad Oblast is a federal subject of Russia . It was established on August 1, 1927, although it was not until 1946 that the oblast's borders had been mostly settled in their present position...

, Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

. The islands are situated at the bottom of the Gulf of Finland

Gulf of Finland

The Gulf of Finland is the easternmost arm of the Baltic Sea. It extends between Finland and Estonia all the way to Saint Petersburg in Russia, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn...

, just outside the town of Primorsk

Primorsk

Primorsk may refer to:*Dənizkənarı, Azerbaijan - formerly Primorsk*Primorsk, Leningrad Oblast, a town in Leningrad Oblast, Russia, formerly Koivisto or Björkö...

 on the Karelian Isthmus

Karelian Isthmus

The Karelian Isthmus is the approximately 45–110 km wide stretch of land, situated between the Gulf of Finland and Lake Ladoga in northwestern Russia, to the north of the River Neva . Its northwestern boundary is the relatively narrow area between the Bay of Vyborg and Lake Ladoga...

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There are 15 islands in the group, the largest is Bolshoy Beryozovy

Bolshoy Beryozovy Island

Bolshoy Beryozovy , alternatively spelled Bolshoy Berezovy, is the largest of the Beryozovye Islands in the Gulf of Finland in Leningrad Oblast, Russia. The island is situated near the Karelian Isthmus, outside the town of Primorsk....

 (Large Berezovy, Finnish: Suuri Koiviston saari). Other islands include Zapadny Beryozovy (West Beryozovy, Finnish: Länsi-Koiviston saari) and Severny Beryozovy (North Beryozovy, Finnish: Pohjois-Koiviston saari). The total area of the group, stretching along the coast for 200 km, is 92 km². They are protected by the state as a seabird sanctuary and one of the Ramsar sites in Russia

Ramsar sites in Russia

there are 35 Ramsar sites in Russia of total area 103,237.67 km2.The first sites were registered with the Ramsar Convention in the Soviet era on October 11, 1976...

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Before the third Swedish crusade

Third Swedish Crusade

The Third Swedish Crusade was a Swedish military expedition to Karelia in 1293, an area controlled by Novgorod. As the result of the attack, Viborg Castle was established and western Karelia remained under Swedish rule for over 400 years....

, the islands paid tax to Novgorod whereupon they became Swedish. In 1721 they became part of Russia, and in 1812 they were restored to the Grand Duchy of Finland

Grand Duchy of Finland

The Grand Duchy of Finland was the predecessor state of modern Finland. It existed 1809–1917 as part of the Russian Empire and was ruled by the Russian czar as Grand Prince.- History :...

 with the county of Viborg

Viborg

Viborg may refer to:*Viborg, Denmark, a city in Jutland, Denmark**Viborg Municipality, a Danish municipality named for the city**Viborg County, a former county of Denmark**Diocese of Viborg**Viborg FF, a professional football team based in Viborg...

. In the independent Finland

Finland

Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

 they belonged to a commune then called Koivisto

Primorsk

Primorsk may refer to:*Dənizkənarı, Azerbaijan - formerly Primorsk*Primorsk, Leningrad Oblast, a town in Leningrad Oblast, Russia, formerly Koivisto or Björkö...

 (Swedish: Björkö). The main settlement on the islands was then called Saarenpää (Krasnoostrovskiy). After WWII, they were ceded by Finland to the Soviet Union

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

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The islands gave name to the Treaty of Björkö

Treaty of Björkö

The Treaty of Björkö, known as the Treaty of Koivisto in modern Finland, was a secret mutual defense accord signed on July 24, 1905 between Wilhelm II of the German Empire and Tsar Nicholas II of Russia.-Secret meeting:...

(1905).