Oder

The Oder (, ; Czech, Lower Sorbian and ;, ; ) is a river in Central Europe. It is Poland's second-longest river in total length and third-longest within its borders after the Vistula and Warta. The Oder rises in the Czech Republic and flows through western Poland, later forming of the border between Poland and Germany as part of the Oder–Neisse line. The river ultimately flows into the Szczecin Lagoon north of Szczecin and then into three branches (the Dziwna, Świna and Peene) that empty into the Bay of Pomerania of the Baltic Sea.
Names.
The Oder is known by several names in different languages, but the modern ones are very similar: English and ; Czech, Polish, and , ; (); Medieval Latin: "Od(d)era"; Renaissance Latin: "Viadrus" (invented in 1534).
Ptolemy knew the modern Oder as the Συήβος ("Suebos"; Latin "Suevus"), a name apparently derived from the Suebi, a Germanic people. While he also refers to an outlet in the area as the Οὐιαδούα "Ouiadoua" (or Οὐιλδούα "Ouildoua"; Latin "Viadua" or "Vildua"), this was apparently the modern Wieprza, as it was said to be a third of the distance between the "Suebos" and Vistula. The name "Suebos" may be preserved in the modern name of the Świna river (German "Swine"), an outlet from the Szczecin Lagoon to the Baltic.
Geography.
The Oder is long: in the Czech Republic, in Poland (including on the border between Germany and Poland) and is the third longest river located within Poland (after the Vistula and Warta), however, second longest river overall taking into account its total length, including parts in neighbouring countries. It drains a basin of , of which are in Poland (89%), in the Czech Republic (6%), and 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 main branch empties into the Szczecin Lagoon near Police, Poland. The Szczecin Lagoon is bordered on the north by the islands of Usedom (west) and Wolin (east). Between these two islands, there is only a narrow channel (Świna) going to the Bay of Pomerania, which forms a part of the Baltic Sea.
The largest city on the Oder is Wrocław, in Lower Silesia.
Navigation.
The Oder is navigable over a large part of its total length, as far upstream as the town of Koźle, where the river connects to the Gliwice 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 the Oder–Spree Canal connects the river to the Spree in Berlin) and Frankfurt upon the Oder. Downstream of Frankfurt the river Warta forms a navigable connection with Poznań and Bydgoszcz for smaller vessels. At Hohensaaten the Oder–Havel Canal 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.
History.
Under Germania Magna the river 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. In Germanic languages, including English, it was and still is called the "Oder", written in medieval Latin documents as "Odera" or "Oddera". Most notably, it was mentioned in the Dagome iudex, which described territory of the Duchy of Poland under Duke Mieszko I in A.D. 990, as a part of duchy's western frontier.
Before Slavs settled along its banks, the Oder was an important trade route, and towns in Germania were documented along with many tribes living between the rivers Albis (Elbe), Oder, and Vistula. Centuries later, after Germanic tribes, the Bavarian Geographer (ca. 845) specified the following West Slavic peoples: Sleenzane, Dadosesani, Opolanie, Lupiglaa, and Golensizi in Silesia and Wolinians with Pyrzycans in Western Pomerania. A document of the Bishopric of Prague (1086) mentions Zlasane, Trebovyane, Poborane, and Dedositze in Silesia.
From the 13th century on, the Oder valley was central to German Ostsiedlung, making the towns on its banks German-speaking over the following centuries.
The Finow Canal, first built in 1605, connects the Oder and Havel. After completion of the more straight Oder–Havel Canal in 1914, its economic relevance decreased.
The earliest important undertaking with a view to improving the waterway was initiated by Frederick the Great, who recommended diverting the river into a new and straight channel in the swampy tract known as Oderbruch near Küstrin. The work was carried out in the years 1746–53, a large tract of marshland being brought under cultivation, a considerable detour cut off and the mainstream successfully confined to a canal.
In the late 19th century, three additional alterations were made to the waterway:
By the Treaty of Versailles, navigation on the Oder became subject to International Commission of the Oder. Following the articles 363 and 364 of the Treaty Czechoslovakia was entitled to lease in Stettin (now Szczecin) its own section in the harbor, then called "Tschechoslowakische Zone im Hafen Stettin". The contract of lease between Czechoslovakia and Germany, and supervised by the United Kingdom, was signed on February 16, 1929, and would end in 2028, however, after 1945 Czechoslovakia did not regain this legal position, de facto abolished in 1938–39.
At the 1943 Tehran Conference the allies decided that the new eastern border of Germany would run along the Oder. However, after World War II, the German areas east of the Oder and the Lusatian Neisse were put under Polish administration by the victorious allies at the Potsdam Conference (at the insistence of the Soviets). As a result, the so-called Oder–Neisse line formed the border between the Soviet occupation zone (from 1949 East Germany) and the areas of Germany under Polish administration. The final border between Germany and Poland was to be determined at a future peace conference. A part of the German population east of these two rivers was evacuated by the Nazis during the war or fled from the approaching Red Army. After the war, the remaining 8 million Germans were forcibly expelled from these territories by the Polish and Soviet administrations. East Germany confirmed the border with Poland under Soviet pressure in the Treaty of Zgorzelec in 1950. West Germany, after a period of refusal, confirmed the inviolability of the border in 1970 in the Treaty of Warsaw. In 1990 newly reunified Germany and the Republic of Poland signed a treaty recognizing the Oder–Neisse line as their border.
Cities.
Main section:
Dziwna branch (between Wolin Island and mainland Poland):
Świna branch (between Wolin and the Usedom islands):
Szczecin Lagoon:
Peene branch (between Usedom Island and the German mainland):