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 is formed by the confluence of the Černa Opava and Stredni Opava streams. Together with the Černa Opava, which is its main source, the Opava is 129.3 km long, making it the 15th longest river in the country. Without the Černa Opava, it is 110.7 km long.
