The Opava ( cs, Opava, pl, Opawa, german: Oppa) is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

in the north-eastern

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

, a left tributary of the Oder river. It originates at the confluence of Bílá (White), Střední (Middle) and Černá (Black) Opava in

Vrbno pod Pradědem Vrbno pod Pradědem (; german: Würbenthal) is a town in Bruntál District in the Moravian-Silesian Region of the Czech Republic. It has about 4,800 inhabitants. Administrative parts Villages and hamlets of Bílý Potok, Mnichov, Vidly and Želez ...

and runs over 110 km (69 mi) to the Oder at

Ostrava Ostrava (; pl, Ostrawa; german: Ostrau ) is a city in the north-east of the Czech Republic, and the capital of the Moravian-Silesian Region. It has about 280,000 inhabitants. It lies from the border with Poland, at the confluences of four riv ...

, with some 25 km (16 mi) forming the border with

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

. Its basin area is about 2,090 km², of which 1,814 km² in the Czech Republic. After the

First Silesian War The First Silesian War (german: Erster Schlesischer Krieg, links=no) was a war between Prussia and Austria that lasted from 1740 to 1742 and resulted in Prussia's seizing most of the region of Silesia (now in south-western Poland) from Austria. T ...

, by the terms of the

Treaty of Breslau The Treaty of Breslau was a preliminary peace agreement signed on 11 June 1742 following long negotiations at the Silesian capital Wrocław (german: Breslau) by emissaries of Archduchess Maria Theresa of Austria and King Frederick II of Prussia ...

in 1742, the Opava in the

Duchy of Troppau The Principality of Opava ( cs, Opavské knížectví; pl, Księstwo Opawskie) or Duchy of Troppau (german: Herzogtum Troppau) was a historic territory split off from the Margraviate of Moravia before 1269 by King Ottokar II of Bohemia to prov ...

became the border between

Austrian Austrian may refer to: * Austrians, someone from Austria or of Austrian descent ** Someone who is considered an Austrian citizen, see Austrian nationality law * Austrian German dialect * Something associated with the country Austria, for example: ...

and

Prussian Prussia, , Old Prussian: ''Prūsa'' or ''Prūsija'' was a German state on the southeast coast of the Baltic Sea. It formed the German Empire under Prussian rule when it united the German states in 1871. It was ''de facto'' dissolved by an e ...

Silesia (the later

Province of Silesia The Province of Silesia (german: Provinz Schlesien; pl, Prowincja Śląska; szl, Prowincyjŏ Ślōnskŏ) was a province of Prussia from 1815 to 1919. The Silesia region was part of the Prussian realm since 1740 and established as an official p ...

). After

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

the demarcation was confirmed by the 1919 Treaty of Saint-Germain-en-Laye as the border between

Czechoslovakia , rue, Чеськословеньско, , yi, טשעכאסלאוואקיי, , common_name = Czechoslovakia , life_span = 1918–19391945–1992 , p1 = Austria-Hungary , image_p1 ...

(

Czech Silesia Czech Silesia (, also , ; cs, České Slezsko; szl, Czeski Ślōnsk; sli, Tschechisch-Schläsing; german: Tschechisch-Schlesien; pl, Śląsk Czeski) is the part of the historical region of Silesia now in the Czech Republic. Czech Silesia is, ...

) and the Second Polish Republic.

Towns

Krnov Krnov (; german: Jägerndorf, pl, Karniów or ''Krnów'') is a town in Bruntál District in the Moravian-Silesian Region of the Czech Republic. It has about 23,000 inhabitants. Administrative parts The town is made up of town parts of Pod Bezr ...

Opava Opava (; german: Troppau, pl, Opawa) is a city in the Moravian-Silesian Region of the Czech Republic. It has about 55,000 inhabitants. It lies on the river Opava. Opava is one of the historical centres of Silesia. It was a historical capital of ...

Kravaře Kravaře (; german: Deutsch Krawarn) is a town in Opava District the Moravian-Silesian Region of the Czech Republic. It has about 6,600 inhabitants. It is part of the historic Hlučín Region. Administrative parts Town parts of Dvořisko and Ko ...

References

Rivers of the Moravian-Silesian Region Rivers of Poland

Moravian-Silesian Region The Moravian-Silesian Region ( cs, Moravskoslezský kraj; pl, Kraj morawsko-śląski; sk, Moravsko-sliezsky kraj) is one of the 14 administrative regions of the Czech Republic. Before May 2001, it was called the Ostrava Region ( cs, Ostravský ...

Rivers of Opole Voivodeship Czech Republic–Poland border International rivers of Europe Border rivers {{Poland-river-stub