The Eider (german: Die Eider; da, Ejderen;

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

: ''Egdor'' or ''Eidora'') is the longest river in the

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

state State may refer to: Arts, entertainment, and media Literature * ''State Magazine'', a monthly magazine published by the U.S. Department of State * ''The State'' (newspaper), a daily newspaper in Columbia, South Carolina, United States * ''Our S ...

Schleswig-Holstein Schleswig-Holstein (; da, Slesvig-Holsten; nds, Sleswig-Holsteen; frr, Slaswik-Holstiinj) is the northernmost of the 16 states of Germany, comprising most of the historical duchy of Holstein and the southern part of the former Duchy of Sch ...

. The river starts near

Bordesholm Bordesholm is a municipality in Schleswig-Holstein, Germany in the district Rendsburg-Eckernförde. ''Bordesholm'' is also the name of a former historical district of the Kingdom of Prussia and Weimar Republic for which it was the district capital ...

and reaches the southwestern outskirts of

Kiel Kiel () is the capital and most populous city in the northern Germany, German state of Schleswig-Holstein, with a population of 246,243 (2021). Kiel lies approximately north of Hamburg. Due to its geographic location in the southeast of the J ...

on the shores of the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and from ...

, but flows to the west, ending in the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...

. The lower part of the Eider was used as part of the

Eider Canal The Eider Canal (also called the Schleswig-Holstein Canal) was an artificial waterway in southern Denmark (later northern Germany) which connected the North Sea with the Baltic Sea by way of the rivers Eider and Levensau. Constructed between 1 ...

until that canal was replaced by the modern

Kiel Canal The Kiel Canal (german: Nord-Ostsee-Kanal, literally "North- oEast alticSea canal", formerly known as the ) is a long freshwater canal in the German state of Schleswig-Holstein. The canal was finished in 1895, but later widened, and links the N ...

. In the

Early Middle Ages The Early Middle Ages (or early medieval period), sometimes controversially referred to as the Dark Ages, is typically regarded by historians as lasting from the late 5th or early 6th century to the 10th century. They marked the start of the Mi ...

the river is believed to have been the border between the related Germanic tribes, the

Jutes The Jutes (), Iuti, or Iutæ ( da, Jyder, non, Jótar, ang, Ēotas) were one of the Germanic tribes who settled in Great Britain after the departure of the Romans. According to Bede, they were one of the three most powerful Germanic nations ...

and the

Angles The Angles ( ang, Ængle, ; la, Angli) were one of the main Germanic peoples who settled in Great Britain in the post-Roman period. They founded several kingdoms of the Heptarchy in Anglo-Saxon England. Their name is the root of the name ' ...

, who along with the neighboring

Saxons The Saxons ( la, Saxones, german: Sachsen, ang, Seaxan, osx, Sahson, nds, Sassen, nl, Saksen) were a group of Germanic * * * * peoples whose name was given in the early Middle Ages to a large country (Old Saxony, la, Saxonia) near the Nor ...

crossed the North Sea from this region during this period and settled in England. During the

High Middle Ages The High Middle Ages, or High Medieval Period, was the periodization, period of European history that lasted from AD 1000 to 1300. The High Middle Ages were preceded by the Early Middle Ages and were followed by the Late Middle Ages, which ended ...

the Eider was the border between the

and the

Danes Danes ( da, danskere, ) are a North Germanic ethnic group and nationality native to Denmark and a modern nation identified with the country of Denmark. This connection may be ancestral, legal, historical, or cultural. Danes generally regard t ...

, as reported by

Adam of Bremen Adam of Bremen ( la, Adamus Bremensis; german: Adam von Bremen) (before 1050 – 12 October 1081/1085) was a German medieval chronicler. He lived and worked in the second half of the eleventh century. Adam is most famous for his chronicle ''Gesta ...

in 1076. For centuries it divided

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Danish Realm, Kingdom of Denmark ...

and the

Holy Roman Empire The Holy Roman Empire was a Polity, political entity in Western Europe, Western, Central Europe, Central, and Southern Europe that developed during the Early Middle Ages and continued until its Dissolution of the Holy Roman Empire, dissolution i ...

. Today it is the border between

Schleswig The Duchy of Schleswig ( da, Hertugdømmet Slesvig; german: Herzogtum Schleswig; nds, Hartogdom Sleswig; frr, Härtochduum Slaswik) was a duchy in Southern Jutland () covering the area between about 60 km (35 miles) north and 70 km ...

Holstein Holstein (; nds, label=Northern Low Saxon, Holsteen; da, Holsten; Latin and historical en, Holsatia, italic=yes) is the region between the rivers Elbe and Eider. It is the southern half of Schleswig-Holstein, the northernmost state of German ...

and Eiderland, the northern and southern parts, respectively, of the modern German state of Schleswig-Holstein. The Eider flows through the following towns: Bordesholm, Kiel,

Rendsburg Rendsburg ( da, Rendsborg, also ''Rensborg'', nds, Rendsborg, also ''Rensborg'') is a town on the River Eider and the Kiel Canal in the central part of Schleswig-Holstein, Germany. It is the capital of the ''Kreis'' (district) of Rendsburg-Ecke ...

Friedrichstadt Friedrichstadt (; da, Frederiksstad) is a town in the district of Nordfriesland, in Schleswig-Holstein, Germany. It is situated on the river Eider approx. 12 km south of Husum. History The town was founded in 1621 by Dutch settlers. Du ...

and

Tönning Tönning (German; Low German ''Tünn'', ''Tönn'' or ''Tönnen''; Danish: ''Tønning''; North Frisian: ''Taning'') is a town in the district of Nordfriesland in the German state of Schleswig-Holstein. History Tönning was destroyed in the Bu ...

. Near Tönning it flows into the North Sea. The

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

has

tidal flats Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal fl ...

and

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estua ...

. The mouth of the river is crossed by a closeable

storm surge barrier A flood barrier, surge barrier or storm surge barrier is a specific type of floodgate, designed to prevent a storm surge or spring tide from flooding the protected area behind the barrier. A surge barrier is almost always part of a larger flood p ...

, the

Eider Barrage The Eider Barrage (german: Eidersperrwerk) is located at the mouth of the river Eider near Tönning on Germany’s North Sea coast. Its main purpose is to protect against storm surges from the North Sea. It is Germany’s largest coastal prot ...

Navigation

A tidal

lock Lock(s) may refer to: Common meanings *Lock and key, a mechanical device used to secure items of importance *Lock (water navigation), a device for boats to transit between different levels of water, as in a canal Arts and entertainment * ''Lock ...

provides access for boats through the

. The fishing port of

lies upstream of the barrier, while

is further upstream. At Friedrichstadt a lock gives access to the River Treene. The Eider remains tidal as far as the lock at Nordfeld, above Friedrichstadt. There is a further lock named near

Wrohm Wrohm is a municipality in the district of Dithmarschen, in Schleswig-Holstein, Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Rus ...

, upstream of Nordfeld. A further beyond Lexfähre is the junction with the short Gieselau Canal, which provides a navigable link to the

Oldenbüttel Oldenbüttel is a municipality in the district of Rendsburg-Eckernförde, in Schleswig-Holstein, Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in ...

. The Eider therefore provides an alternative route from the

to the Kiel Canal, avoiding the tides of the estuary of the

Elbe The Elbe (; cs, Labe ; nds, Ilv or ''Elv''; Upper and dsb, Łobjo) is one of the major rivers of Central Europe. It rises in the Giant Mountains of the northern Czech Republic before traversing much of Bohemia (western half of the Czech Repu ...

. The head of navigation lies a further upstream at

. Although it is adjacent to the Kiel Canal, through passage is no longer possible. Storm tide barrage at the Eider river - photo

References

{{Authority control Rivers of Schleswig-Holstein Holstein Federal waterways in Germany Kiel Canal Rivers of Germany

Navigation

See also

References