The Oder (known in Czech and Polish as Odra) is a river in Central Europe. 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 into three branches (Dziwna, Świna and Peene) that empty into the Baltic Sea.
The Oder is 854 km long: 112 in the Czech Republic, 742 in Poland (including 187 on the border between Germany and Poland) and is the second longest river in Poland (after the Vistula). It drains 118,861 km² of watershed, 106,056 of which are in Poland (89%), 7,217 in the Czech Republic (6%), and 5,587 in Germany (5%). Channels connect it to the Havel, Spree, Vistula system and Kłodnica. It flows through Silesian, Opole, Lower Silesian, Lubusz, and West Pomeranian voivodeships of Poland and the states of Brandenburg and Mecklenburg-Vorpommern in Germany.
The largest city on the Oder River is Wrocław.
The Oder is navigable over a large part of its total length, as far upstream as to the town of Koźle, where the river connects to the Gliwicki Canal. The upstream part of the river is canalized and permits larger barges (up to CEMT Class IV) to navigate between the industrial sites around the Wrocław area.
Further downstream the river is free flowing, passing the towns of Eisenhüttenstadt (where a canal connects the river to the Spree in Berlin) and Frankfurt (Oder). Downstream of Frankfurt the Warta River forms a navigable connection with Poznań and Bydgoszcz for smaller vessels. At Hohensaaten the Havel-Oder-Wasserstrasse connects with the Berlin waterways again.
Near its mouth the Oder reaches the city of Szczecin, a major maritime port. The river finally reaches the Baltic Sea through the Szczecin Lagoon and the river mouth at Świnoujście. (Source: NoorderSoft Waterways Database)
The river in Germania Magna was known to the Romans as the Viadrus or Viadua in Classical Latin, as it was a branch of the Amber Road from the Baltic Sea to the Roman Empire (see via). In German it was and is called the Oder, written in older records as Odera or Oddera in Medieval Latin documents and was mentioned in the Dagome iudex, which described territory of Duke Mieszko I ca. 990 and Oda von Haldensleben.
The Oder was an important trade route and towns in Germania were documented along with many tribes living between the rivers Albis, Viadrus and Vistula. Centuries later the Bavarian Geographer (ca. 845) specifies the following peoples: Silesians, Dadoshanie, Opolanians, Lupiglaa, and Golenshitse in Silesia and Wolinians and Pyrzycans in Western Pomerania. A document of the Bishopric of Prague (1086) mentions Zlasane, Trebovyane, Poborane, and Dedositze in Silesia.
In the 13th century, the first dams were built to protect agricultural lands.
After World War II, the Oder and the Lusatian Neisse formed the Oder-Neisse line, which was designated as the new border between Germany and Poland. The German populations east of these two rivers were expelled westwards.
Dziwna branch (between Wolin Island and mainland Poland):
Świna branch (between Wolin and the Usedom islands):
Peene branch (between Usedom Island and the German mainland):