The Oder (or Odra) River (German: Oder, Polish/Czech: Odra, Ancient Latin: Viadua, Viadrus, Medieval Latin: Odera, Oddera) is a river in Central Europe (mostly in Poland). It begins in the Czech Republic and flows through western Poland, later forming the northern 187 km of the border between Poland and Germany, part of the Oder-Neisse line. The river ultimately flows into the Szczecin Lagoon north of Szczecin and then with three branches (Dziwna, Swina and Peene) that empty into the Baltic Sea.
The Oder River is 854 km long: 112 in the Czech Republic, 742 in Poland (including 187 on the border between Germany and Poland) and second longest river in Poland (after the Vistula). It drains 118,861 square kilometers of watershed, 106,056 of which are in Poland (89%), about 5,587 in Germany (5%), and 7,217 in the Czech Republic (6%). Channels connect it to Havel, Spree, Vistula system and Kłodnica. It flows through Silesian, Opole, Lower Silesian, Lubusz and West Pomeranian voivodships of Poland and Brandenburg and Mecklenburg-Western Pomerania provinces of Germany.
The main branch empties into the Szczecin Lagoon. The Szczecin Lagoon is bordered on the north by islands of Usedom (west) and Wolin (east). Between these two islands, there is only a narrow channel (Swina) going to the Bay of Pomerania, which forms a part of the Baltic Sea.
The greatest city on the Oder River is Wrocław.
The river was known to the ancient Romans as Viadrus, Viadua, as it was a branch of the Amber Road from the Baltic Sea to the Roman Empire. However in the Middle Ages it was called in Latin documents as Odera, Oddera and first mentioned in Dagome Iudex document (ca. 990), describing the boundary of early Poland under duke Mieszko I.
The Oder river must have been an important trade route and human settlement axis as early as 9th or 10th century as the documents mention many tribes living along the river: the Bavarian Geographer (ca. 845) specifies the following peoples: Silesians, Dadoshanie, Opolans, Lupiglaa and Golenshitse in Silesia and also Wolinians and Pyrzycans in Western Pomerania. Document of Prague bishopric (1086) mentions Zlasane, Trebovyane, Poborane and Dedositze in Silesia.
In the 13th century, the first dams were built to protect agricultural lands.
- Brzeg Dolny
- Bytom Odrzanski
- Nowa Sol
- Krosno Odrzańskie
- Frankfurt an der Oder
Dziwna branch (between Wolin island and Polish mainland):
- Kamien Pomorski
Swina branch (between Wolin and Usedom islands):
- Nowe Warpno
Peene branch (between usedom island and the German mainland):
- Olza, Olse
- Mała Panew
- Krzycki Rów
- Warta with Noteć
- Prószkowski Potok
- Nysa Kłodzka
- Średzka Woda
- Cicha Woda
- Biała Woda
- Czarna Struga
- Śląska Ochla
- Zimny Potok
- Lusatian Neisse or Nysa Łużycka
- Geography of the Czech Republic, Geography of Germany, Geography of Poland
- Rivers of the Czech Republic , Rivers of Germany, Rivers of Poland
- Oder-Neisse line
- Lower Odra Valley National Park
- Silesian Voivodship
- Opole Voivodship
- Lower Silesian Voivodship