The Świna is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in Poland

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 flowing from the Oder Lagoon to the Baltic Sea

Baltic Sea

The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

, between the islands of Usedom

Usedom

Usedom is a Baltic Sea island on the border between Germany and Poland. It is situated north of the Szczecin Lagoon estuary of the River Oder in Pomerania...

 and Wolin

Wolin

Wolin is the name both of an island in the Baltic Sea, just off the Polish coast, and a town on that island. It is separated from the island of Usedom by the Świna river, and from mainland Pomerania by the Dziwna river...

. It is a part of the Oder River estuary

Estuary

An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....

, and carries about 75% of that river's waterflow (of the remainder, Peenestrom

Peenestrom

The Peenestrom is a strait or river in Mecklenburg-Vorpommern, Germany. It is 20 Kilometers long and is the westernmost connection of the Szczecin Lagoon with the Baltic Sea. It is therefore also one of the three distributaries of the Oder....

 carries 15% and Dziwna

Dziwna

The Dziwna is an eastern strait, river or a branch of the Oder River out of three straits connecting the Oder Lagoon with the Bay of Pomerania of the Baltic Sea, between the island of Wolin and the Polish mainland.Major towns on the Dziwna include:* Wolin...

 10%). It has a length of about 16 km. Świnoujście

Swinoujscie

Świnoujście is a city and seaport on the Baltic Sea and Szczecin Lagoon, located in the extreme north-west of Poland. It is situated mainly on the islands of Uznam and Wolin, but also occupies smaller islands, of which the largest is Karsibór island, once part of Usedom, now separated by a Piast...

 is a major town on the river.

The German Empire

German Empire

The German Empire refers to Germany during the "Second Reich" period from the unification of Germany and proclamation of Wilhelm I as German Emperor on 18 January 1871, to 1918, when it became a federal republic after defeat in World War I and the abdication of the Emperor, Wilhelm II.The German...

 dammed and deepened the river from 1874-1880 to create the Kaiserfahrt (Piast canal

Piast canal

The Piast Canal - is a canal that connects the Oder Lagoon with the Baltic Sea, more exactly with the northern part of the Świna river. The eastern part of the river is bypassed, providing a more convenient south-north connection for large ships....

). It connected the northern part of the Świna directly with the Oder Lagoon and the Pomerania

Pomerania

Pomerania is a historical region on the south shore of the Baltic Sea. Divided between Germany and Poland, it stretches roughly from the Recknitz River near Stralsund in the West, via the Oder River delta near Szczecin, to the mouth of the Vistula River near Gdańsk in the East...

n harbor of Stettin (Szczecin)

Szczecin

Szczecin , is the capital city of the West Pomeranian Voivodeship in Poland. It is the country's seventh-largest city and the largest seaport in Poland on the Baltic Sea. As of June 2009 the population was 406,427....

. The river thus gained importance as a direct waterway to the industrial city. The territory along the river's path was transferred from Germany to Poland following World War II.