Opava (river)
The Opava is a river in the Czech Republic, a left tributary of the Oder River. It partly forms the Czech-Polish state border. It flows through the Moravian-Silesian Region in the Czech Republic and along the Opole Voivodeship in Poland. It is formed by the confluence of the Černá Opava and Střední Opava streams. Together with the Černá Opava, which is its main source, the Opava is long, making it the 15th longest river in the country. Without the Černá Opava, it is long.
Etymology
The first written mentions of the river are from 1031 and 1062. The words apa, opa were Celtic words for 'water' or 'river'. The suffix -ava is of younger origin and also denotes 'water'. The source streams of the Opava are called Černá Opava, Střední Opava and Bílá Opava.Characteristic
From a water management point of view, the Opava, Černá Opava and Střední Opava are three different watercourses with separate numbering of river kilometres. The Opava itself is formed by the confluence of the Černá Opava and Střední Opava in the territory of Vrbno pod Pradědem at an elevation of, and is long. The stream of Bílá Opava flows to the Střední Opava shortly before its confluence with the Černá Opava and is also considered the source of the Opava.In a broader point of view, the Opava originates in the territory of Zlaté Hory in the Hrubý Jeseník mountain range, on the slope of the Orlík mountain at an elevation of, and flows to Ostrava, where it enters the Oder River at an elevation of. It is long, making it the 15th longest river in the country. The river forms of the Czech-Polish border. Its drainage basin has an area of, of which is in the Czech Republic.
The sources and longest tributaries of the Opava are:
| Tributary | Length | River km | Side |
| Moravice | 100.5 | 35.4 | right |
| Opavice | 35.7 | 71.6 | left |
| Čižina | 23.0 | 56.3 | right |
| Heraltický potok | 18.7 | 51.1 | left |
| Černá Opava | 18.6 | 110.7 | – |
| Velká | 17.2 | 38.8 | right |
| Krasovka | 14.6 | 80.4 | left |
| Střední Opava | 12.9 | 110.7 | right |
Course
The most notable settlement on the river are the cities of Ostrava and Opava, named after the river. The river flows through the municipal territories of Vrbno pod Pradědem, Karlovice, Široká Niva, Nové Heřminovy, Zátor, Brantice, Krnov, Úvalno, Brumovice, Holasovice, Opava, Velké Hoštice, Kravaře, Štítina, Mokré Lazce, Háj ve Slezsku, Dolní Benešov, Kozmice, Dobroslavice, Děhylov, Hlučín and Ostrava.In the section between Krnov and Opava, where the river forms most of the Czech-Polish state border, the river flows along the territory of Gmina Branice.