The Alzette 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...

 with a length of 73 kilometers in France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 and Luxembourg

Luxembourg

Luxembourg , officially the Grand Duchy of Luxembourg , is a landlocked country in western Europe, bordered by Belgium, France, and Germany. It has two principal regions: the Oesling in the North as part of the Ardennes massif, and the Gutland in the south...

. It is a right tributary of the Sauer

Sauer

The Sauer or Sûre is a river in Belgium, Luxembourg and Germany. A left tributary of the river Moselle, its total length is 173 km....

.

It rises in Thil

Thil, Meurthe-et-Moselle

Thil is a commune in the Meurthe-et-Moselle department in north-eastern France.- See also :* Communes of the Meurthe-et-Moselle department...

 near the town Villerupt

Villerupt

Villerupt is a commune in the Meurthe-et-Moselle department in north-eastern France....

 in the Meurthe-et-Moselle

Meurthe-et-Moselle

Meurthe-et-Moselle is a department in the Lorraine region of France, named after the Meurthe and Moselle rivers.- History :Meurthe-et-Moselle was created in 1871 at the end of the Franco-Prussian War from the parts of the former departments of Moselle and Meurthe which remained French...

 département

Départements of France

The departments of France are French administrative divisions. The 101 departments form one of the three levels of local government, together with the 22 metropolitan and 5 overseas regions above them and more than 36 000 communes beneath them...

, France. It crosses the border with Luxembourg after a few kilometres. In Lameschmillen

Lameschmillen

Lameschmillen, also known as the Bergemer Mühle, is located halfway between Bergem and Noertzange , at the confluence of the rivers Alzette and Mess. It is one of three watermills in Luxembourg with the same name. It marks the southern limit of the Dumontshaff Project at Dumontshaff/Dumontshof...

 (near Bergem

Bergem

Bergem is a town in the commune of Mondercange, in south-western Luxembourg. , the town has a population of 1,474. Nearby at Lameschmillen is the confluence of the Alzette and the Mess. In the Middle Ages it belonged to the de Mercy family, together with the aforementioned mill and the castle at...

) it is joined by the Mess

Mess River

The Mess is a river flowing through Luxembourg, joining the Alzette at Lameschmillen, near Bergem. It flows through the towns of Reckange-sur-Mess and Pontpierre....

. It flows through the Luxembourgish towns Esch-sur-Alzette

Esch-sur-Alzette

Esch-sur-Alzette is a commune with city status, in south-western Luxembourg. It is the country's second city, and its second-most populous commune, with a population of 29,853 people...

, Luxembourg City and Mersch

Mersch

Mersch is a commune and town in central Luxembourg, capital of the canton of Mersch. It is situated at the confluence of the rivers Alzette, Mamer and Eisch., the town of Mersch, which lies in the centre of the commune, has a population of 3,345...

, and empties into the Sauer

Sauer

The Sauer or Sûre is a river in Belgium, Luxembourg and Germany. A left tributary of the river Moselle, its total length is 173 km....

 near Ettelbruck

Ettelbruck

Ettelbruck is a commune with city status in central Luxembourg, with a population of approximately 7,500. As of 2005, the town of Ettelbruck itself, which lies in the east of the commune, has a population of 6,191. The town of Warken and Grentzingen are also within the commune...

.

The Sauer is a tributary to the Moselle

Moselle River

The Moselle is a river flowing through France, Luxembourg, and Germany. It is a left tributary of the Rhine, joining the Rhine at Koblenz. A small part of Belgium is also drained by the Mosel through the Our....

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