Teschen Silesia

Cieszyn Silesia or Těšín Silesia or Teschen Silesia (Polish: Śląsk Cieszyński , Czech: Těšínské Slezsko or Těšínsko , German: Teschener Schlesien or Olsagebiet) is a historical region in south-eastern Silesia, centered on the towns of Cieszyn and Český Těšín and bisected by the Olza River. Since 1920 it has been divided between Poland and Czechoslovakia, and later the Czech Republic. It covers an area of about 2,280 square kilometres (880 sq mi) and has about 810,000 inhabitants, of which 1,002 square kilometres (387 sq mi) (44%) is in Poland, while 1,280 square kilometres (494 sq mi) (56%) is in the Czech Republic.

The historical boundaries of the region are roughly the same as those of the former independent Duchy of Teschen/Cieszyn. Currently, over half of Cieszyn Silesia forms one of the euroregions, the Cieszyn Silesia Euroregion, with the rest of it belonging to Euroregion Beskydy.

From an administrative point of view, the Polish part of Cieszyn Silesia lies within the Silesian Voivodeship and comprises Cieszyn County, the western part of Bielsko County, and the western part of the town of Bielsko-Biała.

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