The Lys () or Leie () is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

and

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...

, and a left-bank tributary of the

Scheldt The Scheldt (french: Escaut ; nl, Schelde ) is a river that flows through northern France, western Belgium, and the southwestern part of the Netherlands, with its mouth at the North Sea. Its name is derived from an adjective corresponding to ...

. Its source is in Pas-de-Calais, France, and it flows into the river

Ghent Ghent ( nl, Gent ; french: Gand ; traditional English: Gaunt) is a city and a municipality in the Flemish Region of Belgium. It is the capital and largest city of the East Flanders province, and the third largest in the country, exceeded i ...

, Belgium. Its total length is . Historically a very polluted river from the high population density and industrialisation in both Northern France and Belgium, it has seen substantial improvements in recent years, partly due to the decline of the principal industry, the spinning and weaving of flax. The region of the Leie (between Deinze and Ghent) was known as a favourite place for numerous painters in the first half of the 20th century. The source of the Lys is in a village, Lisbourg, east of Fruges, in the Pas-de-Calais department of France. It flows generally northeast through the following

departments of France In the administrative divisions of France, the department (french: département, ) is one of the three levels of government under the national level (" territorial collectivities"), between the administrative regions and the communes. Ninety ...

, provinces of Belgium and towns and municipalities: * Pas-de-Calais (F):

Thérouanne Thérouanne (; vls, Terenburg; Dutch ''Terwaan'') is a commune in the Pas-de-Calais department in the Hauts-de-France region of France. It is located west of Aire-sur-la-Lys and south of Saint-Omer, on the D 157 and D 341 road junction. Loca ...

, Aire-sur-la-Lys * Nord (F): Merville, Armentières,

Halluin Halluin (; nl, Halewijn) is a commune in the Nord department in northern France. Geography It is located at the north of the Métropole Européenne de Lille, on the Belgian border, contiguous with the Belgian town of Menen. Population Tran ...

* Hainaut (B):

Comines-Warneton Comines-Warneton (; nl, Komen-Waasten, ; pcd, Comène-Warneuton; vls, Koomn-Woastn; wa, Cômene-Varneton) is a city and municipality of Wallonia located in the province of Hainaut, Belgium. On January 1, 2006, it had a total population of 17 ...

West Flanders ) , settlement_type = Province of Belgium , image_flag = Flag of West Flanders.svg , flag_size = , image_shield = Wapen van West-Vlaanderen.svg , shield_size = , image_map ...

(B): Menen, Wevelgem,

Kortrijk Kortrijk ( , ; vls, Kortryk or ''Kortrik''; french: Courtrai ; la, Cortoriacum), sometimes known in English as Courtrai or Courtray ( ), is a Belgian city and municipality in the Flemish province of West Flanders. It is the capital and large ...

, Waregem, Wervik *

East Flanders , native_name_lang = , settlement_type = Province of Belgium , image_flag = Flag of Oost-Vlaanderen.svg , flag_size = , image_shield = Wapen van O ...

(B):

Zulte Zulte () is a Belgian municipality located in Flanders and in the Flemish province of East Flanders. The municipality comprises the towns of Machelen, and Zulte proper. In 2021, Zulte had a total population of 15,843. The total area is 32.52&nbs ...

Deinze Deinze () is a city and a municipality in the Belgian province of East Flanders. It comprises the city of Deinze, and the towns of Astene, Bachte-Maria-Leerne, Gottem, Grammene, Hansbeke, Landegem, Meigem, Merendree, Nevele, Petegem-aan-de-Leie, ...

The main tributaries of the Leie are, from source to mouth:

Laquette The Laquette is a river of northern France, right tributary of the Lys. It is long. It flows into the Lys in Aire-sur-la-Lys Aire-sur-la-Lys (, literally ''Aire on the Lys''; vls, Ariën-aan-de-Leie) is a commune in the Pas-de-Calais d ...

Clarence Clarence may refer to: Places Australia * Clarence County, New South Wales, a Cadastral division * Clarence, New South Wales, a place near Lithgow * Clarence River (New South Wales) * Clarence Strait (Northern Territory) * City of Clarence, a l ...

, Lawe,

Deûle The Deûle (; nl, Deule) is a river of northern France which is channeled for the main part of its course (from Lens to Lille). The upstream part is still partly free-flowing and is known as the Souchez. The Deûle flows into the Lys (right ban ...

, , , and

Mandel Mandel is a surname (and occasional given name) that occurs in multiple cultures and languages. It is a Dutch, German and Jewish surname, meaning "almond", from the Middle High German and Middle Dutch ''mandel''.''Dictionary of American Family Nam ...

. The river was the location of three battles between the Allies and the German Army. During the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

in 1918 the location was the scene of the First Battle of the Lys, which was part of the German Spring Offensive and later that year of the Second Battle of the Lys, which was part of the Allies' Hundred Days Offensive. During the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

, the Battle of the Lys was part of the 1940 German offensive in Flanders towards the English Channel.

History

The Leie/Lys was a commercial navigation from the Middle Ages, but it was the river's devastating floods rather than navigation improvements which justified major works and meander cut-offs started around 1670. The 9 meter difference in elevation between Aire-sur-la-Lys and the border was gradually overcome by six locks and weirs, completed in 1780. The river carried a heavy traffic in grain and linen through to Ghent and Antwerp. The navigation was leased out to a company around 1825, and the locks upgraded to 5.20 m wide, for a draught of 1.60 m. In December 1899, more than 40 schoolchildren skating on the frozen river at Frelinghien fell through the ice and drowned. The river was given its present depth by the Freycinet programme. The section below Armentières was enlarged to class III from 1930, and the border section was improved to class Va starting from 1960. This section is part of the EU's priority project 30 for the Seine-Escaut waterway. The upstream section, by contrast, is used almost exclusively by recreational craft, and is at present heavily silted.

References

External links

River basin of the Lys in FlandersToerisme Leiestreek
{{Authority control International rivers of Europe Rivers of Belgium Rivers of France Rivers of Hauts-de-France Rivers of Nord (French department) Rivers of the Pas-de-Calais Rivers of Flanders Rivers of Wallonia Rivers of East Flanders Rivers of West Flanders Rivers of Hainaut (province)