The Lys () or Leie () is a

river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of ...

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

and

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

, and a left-bank tributary of the

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

. Its source is in

Pas-de-Calais The Pas-de-Calais (, ' strait of Calais'; ; ) is a department in northern France named after the French designation of the Strait of Dover, which it borders. It has the most communes of all the departments of France, with 890, and is the ...

, France, and it flows into the river

, with the confluence in the city of

Ghent Ghent ( ; ; historically known as ''Gaunt'' in English) is a City status in Belgium, city and a Municipalities of Belgium, municipality in the Flemish Region of Belgium. It is the capital and largest city of the Provinces of Belgium, province ...

, 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 Flax, also known as common flax or linseed, is a flowering plant, ''Linum usitatissimum'', in the family Linaceae. It is cultivated as a food and fiber crop in regions of the world with temperate climates. In 2022, France produced 75% of t ...

. 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

department of France. It flows generally northeast through the following

departments of France In the administrative divisions of France, the department (, ) is one of the three levels of government under the national level ("territorial collectivity, territorial collectivities"), between the Regions of France, administrative regions a ...

provinces of Belgium The Kingdom of Belgium is divided into three Communities, regions, and language areas of Belgium, regions. Two of these regions, Flanders and Wallonia, are each subdivided into five provinces. The third region, Brussels, does not belong to any p ...

and towns and municipalities: *

(F):

Thérouanne Thérouanne (; ; Dutch ''Terwaan'') is a commune in the Pas-de-Calais department in the Hauts-de-France region of France west of Aire-sur-la-Lys and south of Saint-Omer, on the river Lys. Population History At the time of the Gauls, ''T ...

Aire-sur-la-Lys Aire-sur-la-Lys (; ; literally "Aire on the Lys (river), Lys") is a Communes of France, commune in the Pas-de-Calais Departments of France, department in northern France. Geography The commune is located 16 kilometres (10 mi) southeast of ...

* Nord (F): Merville,

Armentières Armentières (; , ) is a Communes of France, commune in the Nord (French department), Nord department in the Hauts-de-France region in northern France. It is part of the Métropole Européenne de Lille. The motto of the town is ''Pauvre mais fi� ...

Halluin Halluin (; ) is a Communes of France, commune in the Nord (French department), Nord Departments of France, department in northern France. Geography It is located at the north of the Métropole Européenne de Lille, on the Belgium, Belgian border ...

* Hainaut (B): Comines-Warneton *

West Flanders West Flanders is the westernmost province of the Flemish Region, in Belgium. It is the only coastal Belgian province, facing the North Sea to the northwest. It has land borders with the Dutch province of Zeeland to the northeast, the Flemis ...

(B):

Menen Menen (; ; or ) is a City status in Belgium, city and Municipalities of Belgium, municipality located in the Belgium, Belgian province of West Flanders. The municipality comprises the city of Menen proper and the towns of Lauwe (Belgium), Lau ...

Wevelgem Wevelgem () is a Municipalities of Belgium, municipality located in the Belgium, Belgian province of West Flanders. The municipality comprises the towns of Gullegem, Moorsele and Wevelgem proper. On January 1, 2006, Wevelgem had a total populatio ...

Kortrijk Kortrijk ( , ; or ''Kortrik''; ), sometimes known in English as Courtrai or Courtray ( ), is a Belgian City status in Belgium, city and Municipalities in Belgium, municipality in the Flemish Region, Flemish Provinces of Belgium, province of We ...

, Waregem,

Wervik Wervik (; ; ; ) is a City status in Belgium, city and Municipalities of Belgium, municipality located in the Belgium, Belgian province of West Flanders. The municipality comprises the city of Wervik and the town of Geluwe. On January 1, 2014, We ...

East Flanders East Flanders ( ; ; ; ) is a Provinces of Belgium, province of Belgium. It borders (clockwise from the North) the Netherlands, Dutch province of Zeeland and the Belgian provinces of Antwerp (province), Antwerp, Flemish Brabant, Hainaut (provinc ...

(B):

Zulte Zulte () is a Belgium, Belgian Municipalities of Belgium, municipality located in Flemish Region, Flanders and in the Flanders, Flemish province of East Flanders. The municipality comprises the towns of Machelen (Zulte), Machelen, and Zulte prop ...

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-Lei ...

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

Laquette The Laquette is a river of northern France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre a ...

, Clarence, Lawe,

Deûle The Deûle (; ) 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 bank) in De� ...

, , , and Mandel. The river was the location of three battles between the Allies and the German Army during the two world wars. During the

First World War World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

in 1918 the location was the scene of the First Battle of the Lys, which was part of the

German Spring Offensive The German spring offensive, also known as ''Kaiserschlacht'' ("Kaiser's Battle") or the Ludendorff offensive, was a series of German Empire, German attacks along the Western Front (World War I), Western Front during the World War I, First Wor ...

and later that year of the Second Battle of the Lys, which was part of the Allies'

Hundred Days Offensive The Hundred Days Offensive (8 August to 11 November 1918) was a series of massive Allied offensives that ended the First World War. Beginning with the Battle of Amiens (8–12 August) on the Western Front, the Allies pushed the Imperial Germa ...

. During the

Second World War World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, the Battle of the Lys (1940) was part of the Nazi German Wehrmacht's Blitzkrieg offensive 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 Flanders

Toerisme 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)